Abstract: One embodiment of the present invention relates to a method for transistor matching. In this method, a channel is formed within a first transistor by applying a gate-source bias having a first polarity to the first transistor. The magnitude of a potential barrier in a pocket implant region of the first transistor is reduced by applying a body-source bias having the first polarity to the first transistor. Current flow is facilitated across the channel by applying a drain-source bias having the first polarity to the first transistor. Other methods and circuits are also disclosed.

Abstract: We disclose the structure of a JFET device, the method of making the device and the operation of the device. The device is built near the top of a substrate. It has a buried layer that is electrically communicable to a drain terminal. It has a channel region over the buried layer contacting gate regions that connect to a gate terminal. The channel region, of which the length spans the distance between the buried layer and a source region, is connected to a source terminal. The device current flows in the channel substantially perpendicularly to the top surface of the substrate.

Abstract: A test structure which can be used to detect residual conductive material such as polysilicon which can result from an under etch comprises a PMOS transistor and an OTP EPROM floating gate device. By testing the devices using different testing parameters, it can be determined whether residual conductive material remains subsequent to an etch, and where the residual conductive material is located on the device. A method for testing a semiconductor device using the test structure is also described.

Abstract: An electrically erasable programmable read only memory (EEPROM) (500) is disclosed having improved data retention and read/write endurance. The EEPROM also lacks a more conventional cross coupling arrangement and thus is more area efficient than conventional EEPROM cells. The EEPROM (500) includes a PMOS transistor portion (514a) and an NMOS transistor portion (514b), where respective currents of these devices are compared to one another (e.g., subtracted) to give a differential reading that provides for the state of the EEPROM (500).

Abstract: Capacitor area is increased in the vertical direction by forming capacitors on topographic features on the chip. The features are formed during existing process steps. Adding vertical topography increases capacitance per unit area, reducing die size at no added development cost or mask steps.

Abstract: One embodiment of the present invention relates to a method for transistor matching. In this method, a channel is formed within a first transistor by applying a gate-source bias having a first polarity to the first transistor. The magnitude of a potential barrier in a pocket implant region of the first transistor is reduced by applying a body-source bias having the first polarity to the first transistor. Current flow is facilitated across the channel by applying a drain-source bias having the first polarity to the first transistor. Other methods and circuits are also disclosed.

Abstract: A single-poly EEPROM memory device comprises source and drain regions in a semiconductor body, a floating gate overlying a portion of the source and drain regions, which defines a source-to-floating gate capacitance and a drain-to-floating gate capacitance, wherein the source-to-floating gate capacitance is substantially greater than the drain-to-floating gate capacitance. The source-to-floating gate capacitance is, for example, at least about three times greater than the drain-to-floating gate capacitance to enable the memory device to be electrically programmed or erased by applying a potential between a source electrode and a drain electrode without using a control gate.

Abstract: The disclosure herein pertains to fashioning a low noise junction field effect transistor (JFET) where transistor gate materials are utilized in forming and electrically isolating active areas of a the JFET. More particularly, active regions are self aligned with patterned gate electrode material and sidewall spacers which facilitate desirably locating the active regions in a semiconductor substrate. This mitigates the need for additional materials in the substrate to isolate the active regions from one another, where such additional materials can introduce noise into the JFET. This also allows a layer of gate dielectric material to remain over the surface of the substrate, where the layer of gate dielectric material provides a substantially uniform interface at the surface of the substrate that facilitates uninhibited current flow between the active regions, and thus promotes desired device operation.

Abstract: The formation of a one time programmable (OTP) transistor based electrically programmable read only memory (EPROM) cell (100) is disclosed. The cell (100) includes multiple concentric rings (108, 110) out of which gate structures are formed. An inner transistor based cell (130) formed from the inner ring (108) is shielded from isolation material (106) by one or more outer rings (110). The lack of overlap between the inner transistor and any isolation material promotes enhanced charge/data retention by mitigating high electric fields that may develop at such overlap regions (30, 32).

Abstract: A junction field effect transistor (JFET) is fashioned where a channel of transistor is buried deeply within the workpiece within which the JFET is formed. Burying the channel below the surface of the workpiece and/or away from overlying conductive materials distances a current that flows in the channel from outside influences, such as the effects of the overlying conductive materials. The deep channel also provides a more regular path for the current flowing therein by moving the channel away from non-uniformities on or near the surface of the workpiece, where said non-uniformities or irregularities would interrupt or otherwise disturb current flowing in a channel that is not as deep. These aspects of the deep channel serve to reduce noise and allow the transistor to operate in a more repeatable and predictable manner, among other things.

Abstract: A method forming a current path in a substrate (322) having a first conductivity type is disclosed. The method includes forming an impurity region (314) having a second conductivity type and extending from a face of the substrate to a first depth. A hole (305) is formed in the impurity region. A first dielectric layer (360-364) is formed on an inner surface of the hole. A first electrode (306) is formed in the hole adjacent the dielectric layer.

Abstract: A junction field effect transistor (JFET) is fashioned where a channel of transistor is buried deeply within the workpiece within which the JFET is formed. Burying the channel below the surface of the workpiece and/or away from overlying conductive materials distances a current that flows in the channel from outside influences, such as the effects of the overlying conductive materials. The deep channel also provides a more regular path for the current flowing therein by moving the channel away from non-uniformities on or near the surface of the workpiece, where said non-uniformities or irregularities would interrupt or otherwise disturb current flowing in a channel that is not as deep. These aspects of the deep channel serve to reduce noise and allow the transistor to operate in a more repeatable and predictable manner, among other things.

Abstract: Excessive thinning of a thin oxide in a dual gate CMOS fabrication process is mitigated. A thick gate oxide utilized to form high voltage transistors is selectively patterned to leave some thick oxide in an active area where low voltage transistors are formed. Due to fabrication conditions, the thin gate oxide that is formed in an active area where the low voltage transistors are formed may become too thin, particularly in perimeter areas of the low voltage area. Accordingly, the thick gate oxide is patterned so that some of it remains in perimeter areas of the low voltage active area. This mitigates leakage and/or other unwanted conditions that may result if low voltage transistors are formed using the gate oxide that is too thin.

Abstract: The leakage current of an OTP-EPROM cell formed using buried channel PMOS technology can be reduced. The reduction in leakage current of the OTP-EPROM can be achieved by blocking implantation of the Vtp implant into a channel region of an n-well that substantially underlies a floating gate structure. The Vtp implant can be blocked by providing a mask overlying the surface of the channel region of the n-well during implantation of the Vtp implant.

Abstract: We disclose the structure of a JFET device, the method of making the device and the operation of the device. The device is built near the top of a substrate. It has a buried layer that is electrically communicable to a drain terminal. It has a channel region over the buried layer contacting gate regions that connect to a gate terminal. The channel region, of which the length spans the distance between the buried layer and a source region, is connected to a source terminal. The device current flows in the channel substantially perpendicularly to the top surface of the substrate.

Abstract: We disclose the structure of a JFET device, the method of making the device and the operation of the device. The device is built near the top of a substrate. It has a buried layer that is electrically communicable to a drain terminal. It has a channel region over the buried layer contacting gate regions that connect to a gate terminal. The channel region, of which the length spans the distance between the buried layer and a source region, is connected to a source terminal. The device current flows in the channel substantially perpendicularly to the top surface of the substrate.

Abstract: An electrically erasable programmable read only memory (EEPROM) (500) is disclosed having improved data retention and read/write endurance. The EEPROM also lacks a more conventional cross coupling arrangement and thus is more area efficient than conventional EEPROM cells. The EEPROM (500) includes a PMOS transistor portion (514a) and an NMOS transistor portion (514b), where respective currents of these devices are compared to one another (e.g., subtracted) to give a differential reading that provides for the state of the EEPROM (500).

Abstract: The formation of a one time programmable (OTP) transistor based electrically programmable read only memory (EPROM) cell (100) is disclosed. The cell (100) includes multiple concentric rings (108, 110) out of which gate structures are formed. An inner transistor based cell (130) formed from the inner ring (108) is shielded from isolation material (106) by one or more outer rings (110). The lack of overlap between the inner transistor and any isolation material promotes enhanced charge/data retention by mitigating high electric fields that may develop at such overlap regions (30, 32).

Abstract: The present invention provides a method for monitoring a shift in a buried layer in a semiconductor device. The method for monitoring the shift in the buried layer, among other steps, includes forming a buried layer test structure in, on or over a substrate of a semiconductor device, the buried layer test structure including a first test buried layer located in or on the substrate, the first test buried layer shifted a predetermined distance with respect to a first test feature. The buried layer test structure further includes a second test buried layer lodated in the substrate, the second test buried layer shifted a predetermined but different distance with respect to a second test feature. The method for monitoring the shift in the buried layer may further include applying a test signal to the buried layer test structure to determine an actual shift relative to the predetermined shift.

Abstract: The present invention provides, in one embodiment, a method of reducing 1/f noise in a metal oxide semiconductor (MOS) device (100). The method comprises forming an oxide layer (110) on a silicon substrate (105) and depositing a polysilicon layer (115) on the oxide layer (110). The method further includes implanting a fluorine dopant (130) into the polysilicon layer (115) at an implant dose of at least about 4×1014 atoms/cm2. The polysilicon layer (115) is thermally annealed such that a portion of the fluorine dopant (130) is diffused into the oxide layer (110) to thereby reduce a 1/f noise of the MOS device (100). Other embodiments of the provide a MOS device (300) manufactured by the above-described method and a method of manufacturing an integrated circuit (500) that includes the above-described method.