Abstract: An EPROM memory cell (32) stores information in a floating gate (44) which overlies a portion of a channel between a program drain (36) and a read drain (34). A control gate (46) has a lower segment (48) which overlies the portion of the channel not covered by the floating gate (44), and has an upper portion (50) overlying the floating gate (44). During a program operation, electrons flow from the read drain (34), acting as a source, to the program drain (36), and hot electrons are stored within the floating gate (44). During a read operation, electrons flow from the programming drain (36) to the read drain (34), and the majority of hot electrons drift to the control gate (46). Since the hot electrons do not enter the floating gate (44) during read operations, a higher driving current can be used, thereby increasing the speed at which the EPROM memory cell (32) is read.

Abstract: An array of floating gate memory cells is formed at a face of a semiconductor layer (10). The array includes a plurality of elongate spaced-apart parallel source/drain regions (12). A thick dielectric layer (14) is formed on the face. A plurality of spaced-apart orifices (16) are formed through the thick dielectric layer (14) to the face, each orifice exposing portions of two adjacent source/drain regions (12) and extending therebetween. A plurality of thin first gate insulators (18) are formed on the face in the orifices (16). Next, conductive floating gate electrodes (20) are formed on the orifices (16) and the first gate insulators (18), with the combined thickness of a floating gate electrode (20) and a first gate insulator (18) approximating the thickness of the thick dielectric layer (14). A planarized surface is thus presented for the deposition of an interlevel insulator (22, 24) and a plurality of control gate electrodes (26).

Abstract: One embodiment of the invention provides an EPROM and a method of fabricating an EPROM with enhanced capacitive coupling. Trenched memory cells each comprise a pleat-shaped floating gate with the control gate nested in a fold of the floating gate to increase the coupling ratio with the control gate. As a result higher programming speed and improved cell density may be obtained for a given programming voltage. Formation of bit lines along trench walls results in lower bit line resistivity for a given cell density.

Abstract: A metal-to-polysilicon capacitor, a floating-gate transistor containing such a capacitor, and a method for making the same is disclosed. The bottom plate of the capacitor is formed over a field oxide structure, and the multilevel dielectric is deposited thereover. The multilevel dielectric is removed from the capacitor area, and an oxide/nitride dielectric is deposited over the exposed bottom plate and over the multilevel by way of LPCVD. A first layer of titanium/tungsten is preferably deposited prior to contact etch, and the contacts to moat and unrelated polysilicon are formed. Metallization is sputtered overall, and the metal and titanium/tungsten are cleared to leave the metallization filling the contact holes, and a capacitor having a titanium/tungsten and metal top plate.

Abstract: Disclosed is an integrated circuit process which includes forming two types of active devices: a first set of IGFETs has silicide gates, and the second set has TiN gates. The same TiN thin film layer also provides local interconnect. Optionally the TiN-gate devices may be used for high-voltage devices and the silicide-gate devices used for logic devices. The TiN gates in the second set of transistors and the TiN interconnect are formed by providing a thin film insulator pattern, depositing a titanium layer overall, heating the titanium in a nitrogen bearing atmosphere, and subsequently etching the titanium nitride obtained.

Abstract: A new DRAM structure, wherein the top plate of the storage capacitor is provided by a TiN thin film layer 410', and the bottom plate is provided by a polysilicon layer 402' which also provides the gates 402 of the pass transistors.

Abstract: Disclosed is a floating gate memory array having high-speed programming capabilities. Diffused buried bit lines (14) are formed spaced apart in a semiconductor, forming conduction channels therebetween. Dielectric-filled trenches (24) are formed between the bit lines (14). An insulated floating gate conductor (18) and an insulated control gate conductor (23) are formed over the wafer and patterned to extend over the dielectric-filled trenches (24). The enhanced coupling efficiency between the control gate (23) and the floating gate (18) enhances the programmability of the memory cells.

Abstract: The disclosure relates to a method for reducing filament formation over the BN+ oxide in semiconductor devices wherein a sidewall oxide is formed on the side walls of the first polysilicon layer prior to subsequent formation of the intermediate insulating layer, formation of a second polysilicon layer and subsequent anisotropic etch to provide for removal of all polysilicon over the field oxide.

Abstract: Disclosed is a floating gate memory array having high-speed programming capabilities. Diffused buried bit lines (14) are formed spaced apart in a semiconductor, forming conduction channels therebetween. Dielectric-filled trenches (24) are formed between the bit lines (14). An insulated floating gate conductor (18) and an insulated control gate conductor (23) are formed over the wafer and patterned to extend over the dielectric-filled trenches (24). The enhanced coupling efficiency between the control gate (23) and the floating gate (18) enhances the programmability of the memory cells.

Abstract: An X-cell EEPROM array includes a plurality of common source regions (50) that each border on four gate regions (46), both formed at a face of a semiconductor substrate (10). Each gate region (46) further adjoins a common drain region (52). Each drain region (52) is a common drain for two EEPROM select and memory transistors. A common erase region (54) is implanted into the semiconductor layer (10) in a position remote from the source regions (50) and the drain regions (52). Four floating gate electrodes (40) extend over tunnel windows (22) that are formed on the semiconductor layer (10) in positions adjacent a single erase region (54). An integral contact (64) is made through multilevel oxide (56, 58) from a metal erase line (70) to each erase region (54).

Abstract: A method of forming semiconductor devices wherein a gap is formed beneath the field oxide between the channel stop implant and source/drain regions in the moat or active element region to prevent or minimize encroachment of channel stop impurity toward the source/drain regions to form spurious pn junctions and/or reduce the active element region.

Abstract: The present invention provides a structure and method for fabricating that structure which provides increased capacitance over the prior art while occupying a minimum of surface area of the integrated circuit. The present invention accomplishes this by interleaving multiple capacitor plates to provide increased capacitance while occupying the same surface area as a prior art capacitor providing a fraction of the capacitance provided by the present invention. The present invention is fabricated by providing a capacitor stack which includes interleaved plates of material which may be selectively etched and which is separated by appropriate dielectric material. One portion of the stack is masked while one set of the interleave plates is etched. The etched portion of the interleave plates is filled by a suitable dielectric and a contact is made to the remaining plates. A different portion of the stack is then exposed to an etch which etches the other set of interleave plates.

Abstract: A new integrated circuit structure which includes two types of active devices: a first set of IGFETs has silicide gates, and the second set has TiN gates. The same TiN thin film layer also provides local interconnect. Optionally the TiN-gate devices may be used for high-voltage devices and the silicide-gate devices used for logic devices.

Abstract: An integrated circuit including doubled capacitors (metal/dielectric/TiN/dielectric/polysilicon). This structure is preferably made using a patterned interlevel oxide/nitride layer to split a polycide layer, i.e. at some locations the polycide layer has low sheet resistance and at other locations the polycide layer is vertically split to provide two layers (TiN and unsilicided polysilicon), which are separated by the interlevel oxide/nitride. A double contact etch is used before the first metal interconnect layer is deposited, so that the metal makes ohmic contact to underlying silicide or silicon or TiN in some locations, and in others provides insulated metal top plates over TiN/polysilicon capacitance to provide doubled capacitors.

Abstract: A new integrated circuit structure, wherein a TiN thin film layer 129 and another patterned thin film layer 124 preferably comprising polysilicon are separated (in some locations) by a thin dielectric 132 to define capacitors. At various other locations, the TiN layers 129 also makes contact to the polysilicon layer 124 (which will be silicide-clad at these locations), makes contact to n+ substrate regions 134 and p+ substrate regions 136, and also to provide a contact pad for a third patterned thin film conductor layer which overlies the other two. One important class of embodiments provides a floating-memory cell. wherein the floating gate 120 is made of polysilicon, but the control gate 142 consists predominantly of titanium nitride. A novel process for forming the titanium nitride control gate 142 and simultaneously forming titanium nitride local interconnect lines 149 is also disclosed.

Abstract: The disclosure relates to a method for reducing filament formation over the BN+ oxide in semiconductor devices wherein a sidewall oxide is formed on the side walls of the first polysilicon layer prior to subsequent formation of the intermediate insulating layer, formation of a second polysilicon layer and subsequent anisotropic etch to provide for removal of all polysilicon over the field oxide.

Abstract: The disclosure relates to a method for reducing filament formation over the BN+ oxide in semiconductor devices wherein a sidewall oxide is formed on the side walls of the first polysilicon layer prior to subsequent formation of the intermediate insulating layer, formation of a second polysilicon layer and subsequent anisotropic etch to provide for removal of all polysilicon over the field oxide.

Abstract: An EEPROM cell is described which includes a trench formed in the field oxide adjacent to the EEPROM cell. Both the control gate and the floating gate of the cell are formed over this trench. By forming both gates above the trench, the capacitive coupling between the gates is increased. Thus a EEPROM cell constructed in accordance with the teachings of this invention may be constructed using a smaller surface area of the integrated circuit or may utilize a smaller programming voltage to charge and discharge the floating gate.

Abstract: The present invention provides a structure and method for fabricating that structure which provides increased capacitance over the prior art while occupying a minimum of surface area of the integrated circuit. The present invention accomplishes this by interleaving multiple capacitor plates to provide increased capacitance while occupying the same surface area as a prior art capacitor providing a fraction of the capacitance provided by the present invention. The present invention is fabricated by providing a capacitor stack which includes interleaved plates of material which may be selectively etched and which is separated by appropriate dielectric material. One portion of the stack is masked while one set of the interleave plates is etched. The etched portion of the interleave plates is filled by a suitable dielectric and a contact is made to the remaining plates. A different portion of the stack is then exposed to an etch which etches the other set of interleave plates.

Abstract: Disclosed herein is a process for preparing highly filled acrylic articles comprising:(a) providing a solution of an acid-functional acrylic polymer-in-monomer solution;(b) mixing into said solution a catalytic amount of polymerization promoter system;(c) blending into said mixture 40 percent to 80 percent inert particulate filler to form a casting mixture;(d) introducing said casting mixture to a mold; and(e) curing said molded casting mixture;whereby the viscosity of said casting mixture is controlled and the settling of said filler is minimized by the presence of units from said carboxylic acid in said polymer.