Abstract: The disclosure includes a vertical field-effect transistor (115) with a laterally recessed channel region (92), a vertical field-effect transistor (116) having a graded diffusion junction (31), a static random access memory cell (110) having a vertical n-channel field-effect transistor (116) and a vertical p-channel field-effect transistor (115) and methods of forming them. In one embodiment, a six-transistor static random access memory cell (110) has two pass transistors (111 and 114), which are planar n-channel field-effect transistors, two latch transistors (113 and 116), which are vertical n-channel field-effect transistors with drain regions having graded diffusion junctions (31), and two load transistors (112 and 115), which are vertical p-channel thin-film field-effect transistors having laterally recessed channel regions (92).

Abstract: An interconnect structure is formed having a substrate (10). A conductive layer (14) is formed overlying the substrate (10). A conductive layer (18) is formed overlying the conductive layer (14). An opening (19) is etched through the conductive layer (18), exposing a top portion of conductive layer (14), and forming a sidewall of the conductive layer (18). An selective isotropic etch procedure is used to laterally recess the sidewall of the conductive layer (18). A sidewall spacer (22) is formed adjacent the sidewall of the conductive layer (18). A conductive layer (24) is formed within opening (19) and adjacent the spacer (22) to form an interconnection between conductive layers (24 and 14). The interconnection is self-aligned, and conductive layer (18) is reliably isolated from the interconnect due to the lateral recessed sidewall of the conductive layer (18).

Abstract: A thin film transistor with self-aligned source and drain regions is fabricated, in one embodiment, by forming an opening (124) in a dielectric layer (118) which overlies a substrate (116). A semiconductive sidewall spacer (130) is formed around the perimeter (126) of the opening (124) and adjacent to the sidewall (128) of the opening (124). A first electrode region (120) is electrically coupled to a first portion of the semiconductive sidewall spacer (130) at a first location along the perimeter (126) of the opening (124) which lies only in the second lateral half of the opening (124). A second electrode region (122) is electrically coupled to a second portion of the semiconductive sidewall spacer (130) at a second location along the perimeter (126) of the opening (124) which lies only in the first lateral half of the opening (124). A dielectric layer (132) is formed adjacent to the semiconductive sidewall spacer (130). A control electrode (134) is formed adjacent to the dielectric layer (132).

Abstract: The disclosure includes a vertical field-effect transistor (115) with a laterally recessed channel region (92), a vertical field-effect transistor (116) having a graded diffusion junction (31), a static random access memory cell (110) having a vertical n-channel field-effect transistor (116) and a vertical p-channel field-effect transistor (115) and methods of forming them. In one embodiment, a six-transistor static random access memory cell (110) has two pass transistors (111 and 114), which are planar n-channel field-effect transistors, two latch transistors (113 and 116), which are vertical n-channel field-effect transistors with drain regions having graded diffusion junctions (31), and two load transistors (112 and 115), which are vertical p-channel thin-film field-effect transistors having laterally recessed channel regions (92).

Abstract: A thin film transistor with self-aligned source and drain regions is fabricated, in one embodiment, by forming an opening (124) in a dielectric layer (118) which overlies a substrate (116). A semiconductive sidewall spacer (130) is formed around the perimeter (126) of the opening (124) and adjacent to the sidewall (128) of the opening (124). A first electrode region (120) is electrically coupled to a first portion of the semiconductive sidewall spacer (130) at a first location along the perimeter (126) of the opening (124) which lies only in the second lateral half of the opening (124). A second electrode region (122) is electrically coupled to a second portion of the semiconductive sidewall spacer (130) at a second location along the perimeter (126) of the opening (124) which lies only in the first lateral half of the opening (124). A dielectric layer (132) is formed adjacent to the semiconductive sidewall spacer (130). A control electrode (134) is formed adjacent to the dielectric layer (132).

Abstract: A semiconductor device (20) makes contact between a first metal line (22) and an overlying second metal line (24) without the need for a conductive landing pad. Sidewall spacers (30) are formed adjacent sides of metal lines (22) such that during formation of a via (34) in an overlying dielectric layer (32), the sidewall spacer prevent trenching of underlying dielectric layer (28) if the via is misaligned. The sidewall spacers are formed of a dielectric material which has an etch rate which is significantly slower than the etch rate of dielectric layer (32). In another embodiment, portions of the sidewall spacers are selectively removed prior to depositing a second metal layer (42). Upon depositing the second metal layer, the side of metal line (22) is locally clad with the second metal to increase contact area and lowering contact resistance.

Abstract: A method for forming a planarized layer of material starts by providing a substrate (12). An integrated circuit layer (14) is formed overlying the substrate (12). A first layer of material (16) is formed overlying the integrated circuit layer (14). An etch stop layer (18) is formed overlying the layer of material (16) and etched to form sidewall formations or spacers. A second layer of material (20) is formed overlying the layer of material (16) and the etch stop layer (18). Planarization, polishing, or etch-back processing is performed using the etch stop layer (18) to endpoint. The resulting planarized layer has a thickness which is determined accurately by the etch stop layer (18).

Abstract: A nested surface capacitor and method of formation. The nested surface capacitor has a substrate (14) and an overlying dielectric layer (16). Conductive layer (18) overlies the dielectric layer (16). Three conductive cylindrical structures respectively referred to as an inner cylinder (30), a central cylinder (22') and an outer cylinder (32) overlie the conductive layer (18). The inner cylinder (30) lies within the central cylinder (22'). The central cylinder (22') lies within the outer cylinder (32). Together, the conductive layer (18) and the cylinders (30, 22', and 32) form a first electrode for the nested surface capacitor. A dielectric layer (38) overlying the cylinders (30, 22', and 32) and the conductive layer (18) acts as a capacitor dielectric. A conductive layer (40) overlying the dielectric layer (38) forms a second electrode of the capacitor.

Abstract: An interconnect structure is formed having a substrate (10). A conductive layer (14) is formed overlying the substrate (10). A conductive layer (18) is formed overlying the conductive layer (14). An opening (19) is etched through the conductive layer (18), exposing a top portion of conductive layer (14), and forming a sidewall of the conductive layer (18). An selective isotropic etch procedure is used to laterally recess the sidewall of the conductive layer (18). A sidewall spacer (22) is formed adjacent the sidewall of the conductive layer (18). A conductive layer (24) is formed within opening (19) and adjacent the spacer (22) to form an interconnection between conductive layers (24 and 14). The interconnection is self-aligned, and conductive layer (18) is reliably isolated from the interconnect due to the lateral recessed sidewall of the conductive layer (18).

Abstract: A method requiring only a single mask results in an isolation oxide (50) which is the same size as, instead of becoming larger than, the dimension originally defined by the lithographic system. A buffer layer (14) is formed over the substrate (12). An oxidation resistant layer (16) is formed over the buffer layer (14). The oxidation resistant layer (16) is etched and a disposable sidewall spacer (30) is formed adjacent to the sidewall of the oxidation resistant layer (28), and a trench region is defined (36). The trench region (36) is etched to form a trench. The disposable sidewall spacer (30) is removed and a conformal layer (48) of oxidizable material is deposited over the trench sidewall (40) and the trench bottom surface (38). The conformal layer (48) is then oxidized to form electrical isolation in the isolation regions (26) of the substrate (12).

Abstract: The surface area of a polysilicon electrode is increased by sputtering non-coalescing islands (20) of aluminum onto a silicon dioxide layer (18), which is overlying the polysilicon electrode. The sputtering process allows uniform island formation to be achieved independent of the deposition surface. The non-coalescing islands are then used as a mask, and a portion of the buffer layer (22) and a portion of the polysilicon electrode (26) are etched to form pillar-like regions (30) within the polysilicon electrode.

Abstract: A process for fabricating isolation regions in a semiconductor substrate which does not depend upon pattern definition capability. In one embodiment a device isolation region (30) is formed in a semiconductor substrate (12) by first creating a trench (18) in the substrate (12). A single-crystal SiGe layer (24) is formed to overlie the wall surface (20) of the trench (18). A layer of selectively-deposited, single-crystal silicon (26) is formed in the trench (18) using both the bottom surface (22) of the trench (18) and the SiGe layer (24) as a nucleation site for the selective deposition process. After the single-crystal silicon layer (26) is formed, the SiGe layer (24) is selectively removed and the previously occupied space is filled with a dielectric material to form isolation region (30).

Abstract: A semiconductor device is formed by a process in which a diffusant penetration layer and a diffusant source layer containing a boron dopant are formed overlaying the surface of a semiconductor substrate. The diffusant source layer is annealed to cause the boron dopant to controllably diffuse through the diffusant penetration layer to the semiconductor substrate to form a doped region at the surface. The diffusant source layer and the diffusant penetration layer are removed and a gate insulator is formed on the substrate surface overlaying the doped region. An N doped gate electrode is then formed overlaying the gate insulator.

Abstract: A semiconductor device is disclosed having elevated source and drain regions formed by selectively depositing silicon onto a patterned layer of silicon which acts as a nucleation site for the propagation of the selective deposition process. In accordance with one embodiment of the invention, a silicon substrate is provided of a first conductivity type having an active surface area surrounded by an isolation region. A gate dielectric is formed overlying the active surface area of the substrate and a gate electrode is formed on a central portion of the active surface area. An insulation layer is formed which encapsulates the gate electrode and a first layer of silicon is deposited on the substrate. The first silicon layer is patterned to form a patterned portion overlying the active surface area and the isolation region which is spaced apart from the gate electrode by the insulation layer overlying the gate electrode.

Abstract: A plural transistor structure uses shared electrodes to improve the degree of integration circuits such as SRAMs. The degree of integration is improved by forming a gate of a first transistor from a current electrode, such as a drain of a second transistor with the same region of semiconductor material. Furthermore, a gate of the second transistor can be formed from a drain of the first transistor with the same region of material which dramatically reduces the size of a memory cell latch.

Abstract: A self-aligned one transistor-capacitor memory cell is provided which uses an n-channel MOS transistor having separate drain and source regions with a first level polysilicon conductor coupled to the top plate of the capacitor and separate second level polysilicon conductors coupled to the gate and drain of the transistor. A reduction in a dimension of the memory cell is acheived compared to a similar memory cell which uses only one level of conductors.

Abstract: As integrated field effect devices are scaled to smaller dimensions, the electric field in the channel increases for a constant operating voltage. This induces "hot electron" effects that reduce device reliability. The present invention reduces the voltage (and hence electric field) across one or more transistors in various complementary (e.g. CMOS) logic circuits. This is achieved while still obtaining a full logic swing (e.g., 0-5 volts) at the output of the logic. The technique also allows the retention of previous voltage levels (e.g., 5 volts) for operation of other portions of the integrated circuit (e.g., dynamic memory cells).

Abstract: A dynamic memory obtains reduced leakage currents through the access transistors by preventing the low-going column conductors from reaching zero volts for at least a majority of the duration of the active portion of a memory cycle. The low-going conductors are allowed to reach zero volts during the refresh operation. One advantage is a possible increase in the data storage time between required refresh operations. An increase in the refresh interval is especially useful for memory operations wherein a multiplicity of columns are selected for a given row selection. The present technique also addresses the tendency toward increased sub-threshold leakage as field effect transistor thresholds decrease.

Abstract: A TTL to CMOS input buffer (20) which prevents static current flow when the TTL input signal is at a relatively low voltage logic "1" state. A transition detector (44) responsive to the input TTL logic signal and a voltage boosting circuit (50) connected between a positive power supply (VDD) and the input to a first CMOS inverter (30) are utilized to sense an input signal "0" to "1" transition and boost the TTL logic "1" signal to a voltage level which will prevent the p-channel transistor (32) included in the CMOS inverter from turning "on". The voltage boosting circuit will subsequently be disconnected from the input to the p-channel transistor to prevent the input from being fully charged to the positive power supply.

Abstract: A single ended sense amplifier (10) receives a bit line signal (16) at the gate of a detector MOS transistor (36). The source of the detector transistor (36) is connected to a reference voltage (24) which is adjusted prior to each memory cycle to make the gate to source voltage of the detector transistor (36) equal to the approximate threshold voltage of the transistor. The drain of the detector transistor (36) gates an amplifier transistor (30) which inhibits or passes a read signal (18) to the gate of a digit line pull down transistor (32) which provides an active pull down on a digit line (26) that is precharged to a high voltage prior to a memory read cycle.