Abstract: There is provided a method of manufacturing a semiconductor device including a nonvolatile memory including forming an element isolation area surrounding an element area in a semiconductor substrate doped with a first type conductive impurity, forming a gate insulating film on the element area, forming selectively a cap film on the gate insulating film, burying selectively with a mask film surrounding the cap film on the gate insulating film, forming a tunnel window by removing selectively the cap film, forming an impurity diffusion layer in a surface region of the semiconductor substrate underneath the gate insulating film by introducing a second type conductive impurity using the mask film as a mask, removing the gate insulating film in the tunnel window, forming a tunnel insulating film in the tunnel window, forming a floating gate electrode film, an inter-gate electrode film, and a control gate electrode film on the tunnel insulating film, and forming a source-drain in the semiconductor substrate to inter

Abstract: Methods of fabricating negative-channel metal-oxide semiconductor (NMOS) devices and positive-channel metal-oxide semiconductor (PMOS) devices having complementary threshold voltages are described. Elements of lower-threshold voltage NMOS devices are formed at first locations on a substrate. Elements of higher-threshold voltage PMOS devices are formed at second locations on the substrate. Elements of higher-threshold voltage NMOS devices and elements of lower-threshold PMOS devices are formed by adding a same amount of p-type dopant at selected locations chosen from the first and second locations.

Abstract: A gate electrode is formed over a semiconductor region with a gate insulating film interposed therebetween. An extended high-concentration dopant diffused layer of a first conductivity type is formed in part of the semiconductor region beside the gate electrode through diffusion of a first dopant. A pocket dopant diffused layer of a second conductivity type is formed under the extended high-concentration dopant diffused layer through diffusion of heavy ions. The pocket dopant diffused layer includes a segregated part that has been formed through segregation of the heavy ions.

Abstract: A method of manufacturing a non-volatile memory cell includes forming a bottom dielectric layer and a charge trapping layer on a substrate sequentially. The electron trapping layer is patterned to form a trench exposing a portion of the bottom dielectric layer. A top dielectric layer is formed over the substrate and covers the electron trapping layer and the exposed bottom dielectric layer. A conductive layer is then formed on the top dielectric layer. The conductive layer, the top dielectric layer, the electron trapping layer and the bottom dielectric layer are patterned to form a stacked structure, wherein a width of the stacked structure is larger than a width of the trench. A source/drain region is formed in the substrate adjacent to the edges of the stacked structure. Because the electron trapping layer of the memory cell is divided into two isolation structures according to the invention, it is adapted for the integration of devices and for long-time operation.

Abstract: A nonvolatile semiconductor memory device includes a plurality of memory cells. A couple of bits of data can be stored in the memory cell, the stored data being controlled according to resistance values of first and second variable resistance regions. One of the plurality of memory cells shares its first diffusion layer with an adjacent memory cell and shares its second diffusion layer with another adjacent memory cell. The first diffusion layers of the plurality of memory cells are coupled to each other with a first conductive line extending in a first direction. The second diffusion layers of the plurality of memory cells are coupled to each other with a second conductive line extending in the first direction. The gate electrodes of the plurality of memory cells are coupled to each other with a third conductive line extending in a second direction, which is orthogonal to the first direction.

Abstract: A mask read only memory (ROM) and a method of fabricating the same is provided. This mask ROM and related method is capable of reducing the pitch of buried impurity diffusion regions. In the mask ROM fabrication process, a gate insulation layer is formed over a semiconductor substrate, and parallel conductive layer patterns are formed on the gate insulation layer. These conductive layer patterns are separated from each other by a first predetermined interval and extend in the same direction. Ion implantation is then carried out using the conductive layer patterns as a mask to form buried impurity diffusion regions near the semiconductor substrate between the conductive layer patterns. A conductive layer for use in forming word lines is then formed over the entire surface of the resultant structure, and both the conductive layer and the conductive layer patterns are etched so as to form word lines and pad conductive layers.

Abstract: A fabrication method for a read only memory provides a substrate having a memory cell region and a periphery circuit region. A memory cell region has a memory cell array and the periphery circuit region has transistors. A precise layer having a plurality of first openings is formed in the memory cell region. The first openings are above the channel region of each memory cell in the memory cell array and the critical dimension of the first openings is identical. A mask layer having second openings and third openings is formed on the substrate. The second openings locate over a pre-coding memory cell region, and the third openings locate over the transistor gates. An ion implantation is performed to code the memory cell in the pre-coding memory cell region and to adjust the threshold voltage of the transistor, using the precise layer and the mask layer as a mask.

Abstract: A method for processing dual threshold nMOSFETs and pMOSFETs requiring only one additional masking and implantation operation over single threshold MOSFETs is disclosed. The additional mask and implant operation both enhances the threshold voltage doping of one type of FET and compensates the threshold voltage doping of another type of FET. Where a first threshold voltage implant sets the threshold voltage for an NMOS device to a low threshold voltage, and a second threshold voltage implant sets the threshold voltage for a PMOS device to a high threshold voltage, a third implant may both enhance a NMOS device threshold implant to set the threshold voltage high while compensating a PMOS device threshold implant to set the threshold voltage low.

Abstract: A method of controlling implantation dosages during coding of read-only memory (ROM) devices is disclosed. According to the method, a semi-manufactured ROM device having a plurality of gates with identically designed gate widths is formed, followed by the formation of a first photoresist layer over the semi-manufactured ROM device. The first photoresist layer is selectively exposed to develop a pattern of pre-code openings, with each pre-code opening being positioned over a word line and between two adjacent bit lines intersecting the word line and with the pre-code openings having substantially identical sizes. A second photoresist layer is then formed over the first photoresist layer, followed by selectively exposing the second photoresist layer to develop a pattern of real-code openings therein, with the real-code openings having substantially identical sizes. A tuned dosage of ions is then implanted through intersections of the real-code and pre-code openings to thereby code the ROM device.

Abstract: A process for integrating the fabrication of double diffused drain (DDD) MOSFET devices with the fabrication sub-micron CMOS devices, has been developed. The process features formation of an insulator hard mask shape on an underlying polysilicon gate structure shape in the DDD MOSFET region, while only a polysilicon gate structure shape is formed in the CMOS device region. High energy ion implantation procedures are employed to form the deep source/drain regions of the DDD MOSFET devices with the insulator hard mask shape preventing the high energy implantation procedure from disturbing the underlying channel region. An anneal procedure used activate and drive—in the implanted ions in the deep source/drain region of the DDD MOSFET device is followed by formation of the shallower source/drain regions of the sub-micron CMOS devices.

Abstract: A structure of a 2-bit mask ROM device and a fabrication method thereof are provided. The memory structure includes a substrate, a gate structure, a 2-bit coding implantation region, a spacer, a buried drain region, an isolation structure and a word line. The gate structure is disposed on the substrate, while the coding implantation region is located in the substrate under the side of the gate structure. Further, at least one spacer is arranged beside the side of the gate structure and a buried drain region is disposed in the substrate beside the side of the spacer. Moreover, the buried drain region and the coding implantation region further comprise a buffer region in between. Additionally, an insulation structure is arranged on the substrate that is above the buried drain region, while the word lien is disposed on the gate structure.

Abstract: The present invention provides a code implantation process for the mask read only memory (MROM). A gate oxide layer and a wordline are formed sequentially over a substrate having a buried bitline, with a cap layer formed on the top of the wordline. A dielectric layer is formed on the substrate that is not covered by the wordline and the cap layer. A resist layer with a line/space pattern is formed on the dielectric layer and the cap layer, while the line/space pattern has a first extending direction different to a second extending direction of the cap layer. After removing the cap layer not covered by the resist layer, a code mask layer is formed over the substrate. An ion implantation step is performed to implant dopants into a predetermined code channel region by using the code mask layer, the dielectric layer and the remained cap layer as a mask.

Abstract: Various methods of fabricating halo regions are disclosed. In one aspect, a method of manufacturing is provided that includes forming a symmetric transistor and an asymmetric transistor on a substrate. A first mask is formed on the substrate with a first opening to enable implantation formation of first and second halo regions proximate first and second source/drain regions of the symmetric transistor. First and second halo regions of a first dosage are formed beneath the first gate by implanting off-axis through the first opening. A second mask is formed on the substrate with a second opening to enable implantation formation of a third halo region proximate a source region of the second asymmetric transistor while preventing formation of a halo region proximate a drain region of the asymmetric transistor. A third halo region of a second dosage greater than the first dosage is formed by implanting off-axis through the second opening.

Abstract: LDMOS transistor devices and fabrication methods are provided, in which additional dopants are provided to region of a substrate near a thick dielectric between the channel and the drain to reduce device resistance without significantly impacting breakdown voltage. The extra dopants are added by implantation prior to formation of the thick dielectric, such as before oxidizing silicon in a LOCOS process or following trench formation and before filling the trench in an STI process.

Abstract: An integrated circuit is provided comprising a latch circuit including, a first inverter including a first high threshold voltage PMOS transistor and a first high threshold voltage NMOS transistor with a first data node comprising interconnected source/drains (S/D) of the first PMOS and NMOS transistors; a second inverter including a second high threshold voltage PMOS transistor and a second high threshold voltage NMOS transistor with a second data node comprising interconnected source/drains (S/D) of the second PMOS and NMOS transistors; wherein the gates of the first PMOS and first NMOS transistors are coupled to the second data node; wherein the gates of the second PMOS and second NMOS transistors are coupled to the first data node; a first low threshold voltage access transistor including a first S/D coupled to the first data node and to the gate of the second PMOS transistor and to the gate of the second NMOS transistor and including a second S/D coupled to a first data access node and including a gate c

Abstract: A semiconductor device has at least one high-voltage and low-voltage transistor on a single substrate. The reliability of the high-voltage transistor is enhanced by performing a LDD implantation in only the high-voltage transistor prior to conducting an oxidation process to protect the substrate and gate electrode. After the oxidation process is performed, the low-voltage transistor is subjected to an LDD implantation process. The resultant semiconductor device provides a high-voltage transistor having a deeper LDD region junction depth than the low-voltage transistor, ensuring reliability and performance.

Abstract: A multi-bit Read Only Memory (ROM) cell has a semiconductor substrate of a first conductivity type with a first concentration. A first and second regions of a second conductivity type spaced apart from one another are in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. The ROM cell has one of a plurality of N possible states, where N is greater than 2. The possible states of the ROM cell are determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost.

Abstract: Dot-pattern-like impurity regions are artificially and locally formed in a channel forming region. The impurity regions restrain the expansion of a drain side depletion layer toward the channel forming region to prevent the short channel effect. The impurity regions allow a channel width W to be substantially fined, and the resultant narrow channel effect releases the lowering of a threshold value voltage which is caused by the short channel effect.

Abstract: A substrate is provided having first and second formation areas. An oxide film is formed on both formation areas. An oxidation resistance film is then formed on the oxide film. The second formation area is masked by disposing a photoresist on the oxidation resistance film above the second formation area. The oxidation resistant film is removed from the first formation area and then the photoresist above the second formation area is removed. The oxide film above the first formation area is removed while using the oxidation resistant film above the second formation area as a mask. A first oxide film is formed on the first formation area followed by the removal of the oxidation resistance film above the second formation area. Subsequently, a second oxide film is formed on the second formation area. The first oxide film is designed to have thickness different from the second oxide film.

Abstract: Within a semiconductor fabrication and a method for fabricating the semiconductor fabrication there is provided a series of field effect devices having in a first instance an optional pair of different gate dielectric layer thicknesses, and in a second instance different dopant distribution profiles with respect to a pair of gate electrodes formed upon a pair of gate dielectric layers of a single thickness. The method provides the semiconductor fabrication with multiple gate dielectric layer thicknesses, actual and effective, with enhanced manufacturability and reliability.

Abstract: A method for fabricating a nitride read-only memory. The memory region is integrated with a peripheral circuit region, with a polysilicon layer acting as word line in the memory region to serve as an insulator polishing stop layer with the insulator formed in the first shallow trenches in the peripheral region by disposing an oxide layer, wherein the insulator is simultaneously formed between polysilicon structures in the memory array region to prevent semiconductor substrate reaction with metal such as cobalt during salicidation of the polysilicon, and the ONO layer formed on the sidewalls of the shallow trenches avoids STI corner recess and profile deformation during thermal process.

Abstract: An integrated circuit (IC) is formed on a substrate. The IC has a first well having a first dopant concentration that includes a second conductivity low-voltage transistor. The IC also has a second well having a dopant concentration equal to the first dopant concentration that includes a first conductivity high-voltage transistor. In addition, the IC has a third well having a second dopant concentration of an opposite type than the first well that includes a first conductivity low-voltage transistor. The first conductivity low-voltage transistor and the second conductivity low-voltage transistor are created without a threshold voltage (Vt) implant.

Abstract: A conductor film and a cap insulating film are sequentially formed, and a laminated film constituted of the cap insulating film and the conductor film is patterned, and then a gate electrode is formed. Next, source and drain diffusion regions are formed, and a first silicon nitride film is formed on a sidewall of the laminated film, and then a second silicon nitride film is formed on an entire surface, and further a silicon oxide film is deposited. Next, the silicon oxide film is left between the gate electrodes, and the second silicon nitride film on the laminated film is removed, and the cap insulating film left above the gate electrode is removed, and a metal silicide film is formed on a surface of the gate electrode, and then a third silicon nitride film is left on the gate electrode.

Abstract: A semiconductor device and a method for fabricating the same which improve characteristic of stand-by current of an SRAM cell is disclosed in the present invention.

Abstract: A random access memory cell and fabrication method therefor are disclosed. The random access memory cell includes a first and a second pull-down transistor cross-coupled such that a control terminal of the first pull-down transistor is connected to a conduction terminal of the second pull-down transistors, and the control terminal of the second pull-down transistor is connected to the conduction terminal of the first pull-down transistor. A first pass gate transistor is coupled between the conduction terminal of the first transistor and a first bit line of a bit line pair, and a second pass gate transistor is coupled between the conduction terminal of the second transistor and a second bit line of the bit line pair.

Abstract: A method of forming an MOS integrated circuit having at least two types of NFET, each type having a different threshold voltage, and at least two types of PFET, each type having a different threshold voltage, includes forming at least four active regions in a substrate, each region having a different doping profile. A conventional two threshold voltage CMOS process is modified to produce four transistor threshold voltages with only one additional masked implant operation. This additional implant raises the threshold voltage of one type of MOSFET while lowering that of the other MOSFET type.

Abstract: Methods and apparatus are disclosed for fabricating thick and thin gate oxide transistors in a semiconductor device, wherein lightly doped source/drain regions for the thick gate oxide transistors are formed using a threshold voltage adjust implant, and lightly doped source/drain regions for the thin gate oxide transistors are formed using an LDD implant. The use of threshold voltage implantation to form the lightly doped source/drain regions for the thick gate oxide transistors allows lower dopant concentrations therein compared with the thin gate oxide transistors without the need for separate LDD implantation processing for transistors of different gate oxide thicknesses.

Abstract: A method of fabricating a mask ROM is provided, gate dielectric and a plurality of first conductive strips are sequentially formed over a substrate. A first dielectric layer is formed over the substrate and the first conductive strips. The first dielectric layer is patterned to form a plurality of first coding openings. Each first coding opening exposes the first conductive layer. A plurality of first wells is formed in the first conductive layer at the bottom of the first coding openings. A plurality of second conductive strips is formed over the first dielectric layer and inside the first coding openings to connect electrically with corresponding first wells and form a diode memory cell array. Additional diode memory cell arrays may stack over the diode memory cell array to increase device integration.

Abstract: A semiconductor device (200) comprising a semiconductor substrate (210) having source and drain regions (530, 540) located in the semiconductor substrate (210) and having similar doping profiles, wherein a channel region (550) extends from the source region (530) to the drain region (540). The semiconductor device (200) also comprises a dielectric layer (230) located over the source and drain regions (530, 540), the dielectric layer (230) having first and second thicknesses (T1, T2) wherein the second thickness (T2) is substantially less than the first thickness (T1) and is partially located over the channel region (550). The semiconductor device (200) also comprises a gate (510) located over the dielectric layer (230) wherein the second thickness (T2) is located between an end (515) of the gate (510) and one of the source and drain regions (530, 540).

Abstract: A method of fabricating a mask ROM is provided. gate dielectric and a plurality of first conductive strips are sequentially formed over a substrate. A first dielectric layer is formed over the substrate and the first conductive strips. The first dielectric layer is patterned to form a plurality of first coding openings. Each first coding opening exposes the first conductive layer. A plurality of first wells is formed in the first conductive layer at the bottom of the first coding openings. A plurality of second conductive strips is formed over the first dielectric layer and inside the first coding openings to connect electrically with corresponding first wells and form a diode memory cell array. Additional diode memory cell arrays may stack over the diode memory cell array to increase device integration.

Abstract: Provided is a manufacturing method of a semiconductor integrated circuit device having a plurality of first MISFETs in a first region and a plurality of second MISFETs in a second region, which comprises forming a first insulating film between two adjacent regions of the first MISFET forming regions in the first region and the second MISFET forming regions in the second region; forming a second insulating film over the surface of the semiconductor substrate between the first insulating films in each of the first and second regions; depositing a third insulating film over the second insulating film; forming a first conductive film over the third insulating film in the second region; forming, after removal of the third and second insulating films from the first region, a fourth insulating film over the surface of the semiconductor substrate in the first region; and forming a second conductive film over the fourth insulating film; wherein the third insulating film remains over the first insulating film in the se

Abstract: A method for producing a semiconductor device which comprises causing a dopant present in a semiconductor substrate to segregate in the surface of said semiconductor substrate, thereby forming a thin layer which has a higher dopant concentration than said substrate. The thin layer formed by segregation prevents punch-through which occurs as the result of miniaturization of MOSFET. This method permits economical delta doping without sacrificing the device characteristics.

Abstract: A method of manufacturing an LDMOS transistor includes providing a semiconductor substrate of a first conductivity type having a well region of a second conductivity type formed on a surface of the substrate. Ions of the first conductivity type are implanted into a part of the well region with a predetermined energy. The substrate is subjected to a heat treatment so that the implanted ions are diffused to form a diffusion region of the first conductivity type on the surface of the substrate. Then, a gate oxide layer and a gate electrode are formed on the surface of the substrate. Finally, a drain region is formed on the surface of the substrate. The predetermined energy for the implantation is set so that an accelerated oxidation during a formation of the gate oxide layer is inhibited.

Abstract: A method of forming a semiconductor circuit (20). The method forms a first transistor (NT1) using various steps, such as by forming a first source/drain region (361) as a first doped region in a fixed relationship to a semiconductor substrate (22) and forming a second source/drain region (362) as a second doped region in a fixed relationship to the semiconductor substrate. The second doped region and the first doped region are of a same conductivity type. Additionally, the first transistor is formed by forming a first gate (283) in a fixed relationship to the first source/drain region and the second drain region. The method also forms a second transistor (ST1) using various steps, such as by forming a third source/drain region (341) as a third doped region in a fixed relationship to the semiconductor substrate and forming a fourth source/drain region (342) as a fourth doped region in a fixed relationship to the semiconductor substrate.

Abstract: Mask ROM cell and method of fabricating the same, is disclosed, including a semiconductor substrate of a first conductivity type, a plurality of impurity diffusion regions of a second conductivity type, formed in the semiconductor substrate in one direction, having a predetermined distance therebetween, an insulating layer formed on a portion of the semiconductor substrate, corresponding to each impurity diffusion region, a gate insulating layer formed on the semiconductor substrate, and a plurality of conductive lines formed on the gate insulating layer and insulating layer in a predetermined interval, being perpendicular to the impurity diffusion regions.

Abstract: The present invention provides a method for fabricating a semiconductor device with ultra-shallow super-steep-retrograde epi-channel that is able to overcome limitedly useable energies and to enhance manufacturing productivity than using ultra low energy ion implantation technique that has disadvantage of difficulties to get the enough ion beam current as well as that of prolonged processing time.

Abstract: The present invention includes a 6F2 DRAM array formed on a semiconductor substrate. The memory array includes a first memory cell. The first memory cell includes a first access transistor and a first data storage capacitor. A first load electrode of the first access transistor is coupled to the first data storage capacitor via a first storage node formed on the substrate. The memory array also includes a second memory cell. The second memory cell includes a second access transistor and a second data storage capacitor. A first load electrode of the second access transistor is coupled to the second data storage capacitor via a second storage node formed on the substrate. The first and second access transistors have a gate dielectric having a first thickness. The memory array further includes an isolation gate formed between the first and second storage nodes and configured to provide electrical isolation therebetween.

Abstract: A fabrication method for a read only memory provides a substrate having a memory cell region and a periphery circuit region. A memory cell region has a memory cell array and the periphery circuit region has transistors. A precise layer having a plurality of first openings is formed in the memory cell region. The first openings are above the channel region of each memory cell in the memory cell array and the critical dimension of the first openings is identical. A mask layer having second openings and third openings is formed on the substrate. The second openings locate over a pre-coding memory cell region, and the third openings locate over the transistor gates. An ion implantation is performed to code the memory cell in the pre-coding memory cell region and to adjust the threshold voltage of the transistor, using the precise layer and the mask layer as a mask.

Abstract: This invention relates to a method for fabricating a semiconductor device with the epi-channel structure, which is adapted to overcome an available energy limitation and to improve the productivity by providing the method of SSR epi Channel doping by boron-fluoride compound ion implantation without using ultra low energy ion implantation and a method for fabricating the semiconductive device with epi-channel structure adapted to prevent the crystal defects caused by the epitaxial growth on ion bombarded and fluorinated channel doping layer.

Abstract: An integrated semiconductor system is provided that is formed on a substrate 10. A dual implant mask 26 is used to change the characteristics of semiconductor devices formed in regions of the substrate 10 having different characteristics. Transistors 50 and 52 can be formed on the same substrate 10 and have different electrical characteristics.

Abstract: The present invention provides a method for manufacturing a semiconductor device, an associated method for manufacturing an integrated circuit, and an LDMOS device manufactured in accordance with the method for manufacturing the semiconductor device. The method for manufacturing the semiconductor device, in one embodiment, may include depositing a layer of photoresist material over a substrate and creating an active device opening having sidewall angles associated therewith through the photoresist material. Additionally, the method may include forming a dummy opening through the photoresist material, wherein the dummy opening is located proximate the active device opening to reduce a shrinkage of the photoresist between the dummy opening and the active device opening and thereby inhibit nonuniform distortion of the sidewall angles.

Abstract: A mask read-only-memory structure and its method of manufacture are provided. The structure includes a substrate, a buried bit line in the substrate and a patterned stack layer covering a portion of the upper surface of the substrate. The stack layer includes a first dielectric layer, a stopping layer and a second dielectric layer. A gate oxide layer covers a portion of the upper surface of the substrate. A word line runs across the buried bit line to form a plurality of coding cells. The memory cells having a stack layer thereon are at a logic state “0” while the memory cells having a gate oxide layer thereon are at a logic state “1”.

Abstract: Disabling flash memory cells to protect their contents, and thus essentially transforming them into read-only memory (ROM) cells, is disclosed. A gate mask and an implant code mask are positioned over a given flash memory cell. A field oxide layer is then fabricated within a substrate layer of the cell through the masks as logically and'ed together. By such fabrication, the flash memory cell is at least partially disabled. The masks are preferably a gate mask and an implant code mask, as these masks typically are already existing and available for use.

Abstract: A mask ROM device is described. The mask ROM device includes a substrate, a gate, a double diffused source/drain region that comprises a first doped region and a second doped region, a channel region, a coding region, a dielectric layer and a word line. The gate is disposed on the substrate. The double diffused source/drain region is positioned beside the sides of the gate in the substrate, wherein the second doped region is located at the periphery of the first doped region in the substrate. The channel region is located between the double diffused source/drain region in the substrate. The coding region is disposed in the substrate at the intersection between the sides of the channel region and the double diffused source/drain region. The dielectric layer is disposed above the double diffused source/drain region, while the word line is disposed above the dielectric layer and the gate.

Abstract: A method of manufacturing mask ROM is provided. A buried bit line is formed in a substrate and then a gate and a word line are formed over the substrate. Thereafter, a pre-coding layer with a plurality of pre-coding openings therein is formed over the substrate in a relatively high precision process. The pre-coding openings correspond in position to a plurality of coding regions on the substrate underneath the gate. A filler material is deposited into the pre-coding openings to form a filler layer. A coding mask having a plurality of coding openings is formed over the substrate in a relatively low precision process. The filler material inside the pre-coding openings that correspond in position to the code openings in the coding mask is removed. The coding mask is removed. Finally, a coding ion implant is carried out using the pre-coding layer and the filler layer as mask and hence ions are implanted into the code region through the pre-coding openings.

Abstract: A semiconductor circuit with a depletion-mode transistor is formed with a method that eliminates the need for a separate mask and implant step to set the threshold voltage of the depletion-mode transistor. As a result, the method of the present invention reduces the cost and complexity associated with the fabrication of a semiconductor circuit that includes a depletion-mode transistor.

Abstract: A method of code programming a mask read only memory (ROM) is disclosed. According to the method, a first photoresist layer is formed over word lines and a gate oxide layer of a substrate already having implanted bit lines. The first photoresist layer is patterned to develop pre-code openings over all of the memory cells, which correspond to intersecting word and bit lines. The first photoresist layer is then hardened using either a treatment implant or a treatment plasma. Subsequently, a second photoresist layer is formed over the first photoresist layer and patterned to develop real-code openings over memory cells which are actually to be coded with a logic “0” value. Each memory cell to be coded is then implanted with implants passing through the pre-code openings and the real code openings and into the memory cell.

Abstract: A power MOSFET is provided that includes a substrate of a first conductivity type. An epitaxial layer also of the first conductivity type is deposited on the substrate. First and second body regions are located in the epitaxial layer and define a drift region between them. The body regions have a second conductivity type. First and second source regions of the first conductivity type are respectively located in the first and second body regions. A plurality of trenches are located below the body regions in the drift region of the epitaxial layer. The trenches, which extend toward the substrate from the first and second body regions, are filled with a material that includes a dopant of the second conductivity type. The dopant is diffused from the trenches into portions of the epitaxial layer adjacent the trenches.

Abstract: A low threshold voltage NMIS area and a high threshold voltage PMIS area are set by a photoresist mask also used for well formation. Using a photoresist mask with openings for the NMIS and PMIS, the NMIS and PMIS areas are set by one ion implantation step. After gate oxidation, ion implantation is conducted through an amorphous silicon film onto wells, channels, and gate electrodes. A plurality of CMIS threshold voltages can be set and the gate electrodes of both polarities can be formed in a reduced number of steps using photoresist. This solves the problem in which photomasks are required as many as there are ion implantation types for wells, channel stoppers, gate electrodes, and threshold voltage control and hence the number of manufacturing steps and the production cost are increased.

Abstract: A non-volatile memory device including a plurality of memory cells, each memory cell formed as MOS transistor with a source region, a drain region and a gate having sides formed therewith; and one or more dielectric spacers disposed on the sides of the gate. At least one memory cell is defined in an ON state and at least one memory cell is defined in an OFF state. The memory cells in the ON state comprise drain regions and source regions of the lightly diffused drain (LDD) type, characterized in that the at least one drain region and the at least one source region of the memory cells in the OFF state are formed by one or more high dopant regions. The memory cells in the OFF state consists of layers of silicide on top of one or more active regions defined as the source region, the drain region, and the gate.