摘要:
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).
摘要:
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).
摘要:
A floating gate (51) is formed to have a cavity (52) that increases the capacitive coupling between the floating gate (51) and a control gate for the memory cell. The memory cell may be used in EPROM, EEPROM, and flash EEPROM arrays and may be programmed and erased by hot carrier injection, Fowler-Nordheim tunneling or the like. The process sequence for forming the cavity (52) of the floating gate (51) has good process margin allowing some lithographic misalignment. In one embodiment, a multi-tiered floating gate may be formed. The multi-tier structure allows the capacitive coupling to further increase without occupying more area.
摘要:
A floating gate (51)is formed to have a cavity (52) that increases the capacitive coupling between the floating gate (51) and a control gate for the memory cell. The memory cell may be used in EPROM, EEPROM, and flash EEPROM arrays and may be programmed and erased by hot carrier injection, Fowler-Nordheim tunneling or the like. The process sequence for forming the cavity (52) of the floating gate (51) has good process margin allowing some lithographic misalignment. In one embodiment, a multi-tiered floating gate may be formed. The multi-tier structure allows the capacitive coupling to further increase without occupying more area.
摘要:
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).
摘要:
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.
摘要:
A silicon-on insulator film (38) is formed by solid phase epitaxial re-growth. A layer of amorphous silicon (36) is formed such that it is only in direct contact with an underlying portion of a silicon substrate (12). The layer of amorphous silicon (36) is subsequently annealed to form a monocrystalline layer of epitaxial silicon (38). Because the amorphous silicon layer (36) is in contact with only the silicon substrate (12), during the re-growth process, the resulting epitaxial layer (38) is formed with a reduced number of crystal defects. The resulting epitaxial silicon layer (38) may then be used to form semiconductor devices.
摘要:
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).
摘要:
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. A second layer of electrically conductive material is selectively deposited using the patterned portion of the first silicon layer as a nucleation site and an impurity of a second conductivity type is introduced into the second layer of silicon. The selectively deposited layer of electrically conductive material forms elevated source and drain regions which make electrical contact with the active surface area and are electrically insulated from the gate electrode by the insulation layer encapsulating the gate electrode.
摘要:
A semiconductor device is provided that includes a fin having a first gate and a second gate formed on a first sidewall of the fin in a first trench, wherein the first gate is formed above the second gate. The device includes a third gate and a fourth gate formed on a second sidewall of the fin in a second trench, wherein the third gate is formed above the fourth gate. Methods of manufacturing and operating the device are also included. A method of operation may include biasing the first gate and the fourth gate to create a current path across the fin.