Abstract: A method for fabricating MOSFETs with a recessed self-aligned silicide contact and extended source/drain junctions is described. A gate structure having a gate insulating layer, a first conductive layer and a first dielectric layer is formed on a substrate. A thermal oxide layer is formed on the substrate and on sidewalls of the first conductive layer. The first dielectric layer is removed. Extended source and drain junctions are formed in the substrate under a region covered by the first thermal oxide layer. Sidewall spacers are formed on the sidewalls of the gate structure to protect the extended source and drain junctions therebeneath from being silicided. The second thermal oxide layer is removed to form recessed regions on a substrate surface. A first metal layer is formed on the substrate after the first dielectric layer is removed. Source/drain regions under the recessed regions are formed.

Abstract: A method of forming MOSFET with buried contacts and air-gap gate structure is disclosed. The method comprises following steps firstly, a gate is formed of pad oxide layer and a nitride layer sequentially on a silicon substrate, which has trench isolations. Then, a polysilicon layer and an oxide layer are deposited in order on all areas. Subsequently, an etched-back using the nitride layer a stopping layer is achieved. After that the nitride layer is removed thereby, forming a gate hollow region. After the pad oxide layer is removed, an oxynitride layer is regrown to be as the gate oxide. Thereafter, a silicon is deposited on all areas and refills in the gate hollow region. A planarization process is again performed using the oxide layer as an etch-stopping layer. Subsequently, the oxide layer is removed. S/D/G ion implanted into the polysilicon layer and the silicon layer. Then, the nitride spacers are removed to form dual recessed spaces.

Abstract: The proposed method of the present invention forms MOSFETs with improved short channel effects and operating speeds over conventional devices. The method for fabricating MOSFETs includes the following steps. At first, isolation regions are formed on a semiconductor substrate and a gate insulating layer is formed on the substrate. A first conductive layer is then formed on the gate insulating layer and a first dielectric layer is formed on the first conductive layer. A removing process is performed to remove portions of the gate insulating layer, the first conductive layer and the first dielectric layer to define a gate structure. A layer formation step is carried out to form a thermal oxide layer on the substrate and on sidewalls the first conductive layer. Doped dielectric sidewall spacers are then formed on sidewalls of the gate structure. A removing step is carried out to remove portions of the thermal oxide layer uncovered by the doped dieletric sidewall spacers.

Abstract: The method for forming an isolation region in the present invention mainly includes the following steps. First, a pad layer is formed on a semiconductor substrate and an oxidation masking layer is formed on the pad layer. The oxidation masking layer, the pad layer, and the substrate are then patterned to form trenches in the substrate. The pad layer is removed laterally to form undercut structures under the oxidation masking layer. A doped layer is conformably formed on the oxidation masking layer, the undercut structures of the pad layer, and the substrate in the trenches. Next, a thermally oxidizing step is carried out to oxidize the doped layer to form an oxidized layer conformably on the oxidation masking layer, the undercut structures of the pad layer, and the substrate in the trenchs. A dielectric layer is formed over the substrate to fill up the trenches and cover over the pad layer and the oxidation masking layer. The dielectric layer is planarized downward to portions of the oxidation masking layer.

Abstract: The present invention proposes a shallow trench isolation region in a semiconductor substrate for ULSI devices. The trench region includes a thermal oxide film formed on the bottom and the sidewall, a CVD dielectric film formed on the bottom of the thermal oxide film, and a channel stop region formed beneath the bottom of the thermal oxide film. The processes described as follows. Forming a pad oxide/silicon nitride layer on the substrate, the trench region and active area are defined. After silicon spacers are formed, the silicon substrate is recessed to form trench region by using the silicon nitride layer and silicon spacers as etching mask. A channel stopping implantation is performed. Then a thermal oxide film is regrown on the trench surface. After removing the silicon nitride layer, a thick CVD dielectric layer is deposited on the substrate. The dielectric film outside the trench region is removed by a CMP process, and thus the present invention complete.

Abstract: A method for fabricating MOSFETs with a recessed self-aligned silicide contact and extended source/drain junctions is described. A gate structure having a gate insulating layer, a first conductive layer and a first dielectric layer is formed on a substrate. A thermal oxide layer is formed on the substrate and on sidewalls of the first conductive layer. Sidewall spacers are formed on sidewalls of the gate structure. The thermal oxide layer uncovered by the sidewall spacers is removed. The substrate is isotropically etched to form recessed regions on the substrate in regions uncovered by the gate structure and the sidewall spacers. A first metal layer is formed on the substrate after the first dielectric layer is removed. A source/drain/gate implantation is performed to the substrate, thereby forming source/drain regions under the recessed regions.

Abstract: A gate insulator layer is formed over the semiconductor substrate and a first silicon layer is then formed over the gate insulator layer. A first dielectric layer is formed over the first silicon layer. A gate region is defined by removing a portion of the gate insulator layer, the first silicon layer, and the first dielectric layer. A doping step using low energy implantation or plasma immersion is carried out to dope the substrate to form an extended source/drain junction in the substrate under a region uncovered by the gate region. An undoped spacer structure is formed on sidewalls of the gate region and the first dielectric layer is removed. A second silicon layer is formed on the semiconductor substrate and on the first silicon layer. Another doping step is performed to dope the second silicon layer. A series of process is then performed to form a metal silicide layer on the second silicon layer and also to diffuse and activate the doped dopants.

Abstract: The present invention proposes a shallow trench isolation region in a semiconductor substrate for ULSI devices. The trench region includes a thermal oxide film formed on the bottom and the sidewall, a CVD dielectric film formed on the bottom of the thermal oxide film, and a channel stop region formed beneath the bottom of the thermal oxide film. The processes described as follows. Forming a pad oxide/silicon nitride layer on the substrate, the trench region and active area are defined. After silicon spacers are formed, the silicon substrate is recessed to form trench region by using the silicon nitride layer and silicon spacers as etching mask. A channel stopping implantation is performed. Then a thermal oxide film is regrown on the trench surface. After removing the silicon nitride layer, a thick CVD dielectric layer is deposited on the substrate. The dielectric film outside the trench region is removed by a CMP process, and thus the present invention complete.

Abstract: The present invention discloses a method to form CMOS transistors for high speed and lower power applications. A high energy and low dose phosphorous is implanted in a silicon substrate to fabricate an N-well after a pad oxide layer and a silicon nitride layer is formed. After a thick field oxide is formed by using a high temperature steam oxidation process, another high energy and low dose multiple boron implantation is then performed to fabricate a buried heavily boron doped region. A rapid thermal processing (RTP) system is following used to activate the boron dopant to form buried p+ layer and to recover the implanted damages. All the field oxide films are then removed by using a diluted HF or BOE solution. After porous silicon is obtained via anodic electrochemical dissolution in the HF solution, the porous silicon is then thermally oxidized to form the separate n-type silicon islands. Next, a thick CVD oxide film is deposited and then etched back to planarize device surface.

Abstract: In the preferred embodiment for forming a ragged polysilicon crown-shaped capacitor of a memory cell, a first dielectric layer is formed on a semiconductor substrate. A portion of the first dielectric layer is removed to define a contact hole within the first dielectric layer, wherein the contact hole is extended down to a source region in the substrate. Next, a conductive plug is formed and is communicated to the source region within the contact hole. A second dielectric layer is formed on the first dielectric layer and the conductive plug, and a third dielectric layer is formed on the second dielectric layer. Next, portions of the third dielectric layer and the second dielectric layer are removed to define a storage node opening, wherein the storage node opening is located over the conductive plug. A first conductive layer is then formed to conformably cover the inside surface of the storage node opening and on the third dielectric layer.

Abstract: The method of the present invention is to fabricate a CMOS device without boron penetration. A nitrided gate oxide and SAS gate electrode are provided to suppress boron penetration. The nitrided gate oxide could be formed in two approaches. One of the approaches is to implant nitrogen ions into the interface between substrate and pad oxide layer, and then thermally treat the substrate for segregating the doped nitrogen ions in the surface of substrate. Removing the pad oxide layer, thermally treating the substrate in oxygen ambient for growing a gate oxide layer, the nitrided gate oxide layer is formed by incorporating doped nitrogen ions into the growing gate oxide layer. The other approach is to place the substrate having a gate oxide layer thereon in nitrogen plasma ambient, thereby forming the nitrided gate oxide layer. After the formation of nitrided gate oxide layer, at least one stacked amorphous silicon (SAS) layer is formed over the gate oxide layer.

Abstract: The method for forming flash memory includes the following steps. At first, a semiconductor substrate with an isolation region formed upon is provided. The semiconductor substrate has a pad oxide layer and a first nitride layer formed over. A portion of the first nitride layer and of the pad oxide layer are removed to define a gate region. A first oxide layer is formed and then a sidewall structure is formed. The semiconductor substrate is doped with first type dopants. A first thermal process is performed to form a second oxide layer and drive in the first type dopants. The sidewall structure and the first nitride layer are then removed, and the first oxide layer is removed to expose a portion of the substrate under the first oxide layer. Silicon grains are formed on the pad oxide layer, the exposed portion of substrate, and the second oxide layer. The exposed portion of the substrate is then etched to leave a rugged surface on the exposed portion of the substrate.

Abstract: The present invention discloses a method of forming CMOS transistors with self-aligned planarization twin-well by using fewer mask counts. After a silicon nitride layer is formed over a first pad oxide layer on a semiconductor substrate, an N-well region is defined by first implanting in the semiconductor substrate. After removing the first photoresist layer, a second ion implantation is performed to define a P-well region. Next, both the silicon nitride layer and the first pad oxide layer are removed. A high temperature long time anneal is done to form a deep twin-well. A plurality of LPD oxide trench isolation regions is formed to define an active area region. A second pad oxide layer is formed on the substrate. Finally, the standard processes can be employed for fabricating the CMOS transistors on the substrate.

Abstract: The present invention discloses a method of forming CMOS transistors with self-aligned planarization twin-well by using fewer mask counts. After a silicon nitride layer is formed over a first pad oxide layer on a semiconductor substrate, an N-well region is defined by first implanting in the semiconductor substrate. After removing the first photoresist layer, a second ion implantation is performed to define a P-well region. Next, both the silicon nitride layer and the first pad oxide layer are removed. A high temperature long time anneal is done to form a deep twin-well. A plurality of trench isolation regions is formed to define an active area region. A second pad oxide layer is formed on the substrate. A high energy and low dose blanket phosphorous is implanted in a semiconductor substrate for forming a punch-through stopping layer of the PMOSFET device. A low energy and low dose blanket BF2 implant then adjust both the threshold voltages of the PMOSFET and NMOSFET.

Abstract: A gate insulator layer is formed over the semiconductor substrate and a first silicon layer is then formed over the gate insulator layer. An first dielectric layer is formed over the first silicon layer. A gate region is defined by removing a portion of the gate insulator layer, of the first silicon layer, and of the first dielectric layer. A doping step using low energy implantation or plasma immersion is carried out to dope the substrate to form an extended source/drain junction in the substrate under a region uncovered by the gate region. An undoped spacer structure is formed on sidewalls of the gate region and a second silicon layer is formed on the semiconductor substrate. The first silicon layer is then removed and another doping step is performed to dope the first silicon layer and the second silicon layer. A series of process is then performed to form a metal silicide layer on the first silicon layer and the second silicon layer and also to diffuse and activate the doped dopants.

Abstract: The method of the present invention includes the following steps. First, a gate oxide layer is formed on the substrate. An undoped polysilicon layer is formed over the gate oxide layer. Then, a first dielectric layer is formed over the undoped polysilicon layer. A photoresist layer is formed over the first dielectric layer. Next, the photoresist layer is patterned to define a gate region. An etching process is performed to the photoresist layer to narrow the gate region. Portions of the first dielectric layer are etched using the residual photoresist layer as a mask. The undoped polysilicon layer is etched using the residual photoresist layer and the residual first dielectric layer as a mask. Then, a PSG is layer deposited over the residual first dielectric layer and the substrate. Subsequently, the PSG layer is etched back to form side-wall spacers to serve as ion diffusion source. A noble or refractory metal layer is deposited on all areas of the substrate.

Abstract: A structure of a capacitor on a semiconductor wafer including the following structure is disclosed herein. A first electrode including a flower structure is formed on the semiconductor wafer. The first electrode includes a flower neck portion, a flower bottom portion, and a flower top portion. The flower neck portion is electrically coupled to the semiconductor wafer. The flower bottom portion is electrically coupled to the flower neck portion, in which the flower bottom portion includes a first protudent portion. The flower top portion includes a downward hemispherical portion and a second protrudent portion, and is electrically coupled to the flower neck portion. The flower bottom portion is formed of titanium nitride, and the flower top portion is formed of Ti/TiN or TiW. A first dielectric film is formed on the first electrode, and the first dielectric layer is the dielectric layer of the capacitor. A second electrode is formed on the first dielectric film.

Abstract: In the preferred embodiment for forming a ragged polysilicon crown-shaped capacitor of a memory cell, a first dielectric layer is formed on a semiconductor substrate. A portion of the first dielectric layer is removed to define a contact hole within the first dielectric layer, wherein the contact hole is extended down to a source region in the substrate. Next, a conductive plug is formed and communicated to the source region within the contact hole. A second dielectric layer is formed on the first dielectric layer and the conductive plug, and a third dielectric layer is formed on the second dielectric layer. Next, portions of the third dielectric layer and the second dielectric layer are removed to define a storage node opening, wherein the storage node opening is located over the conductive plug. A first conductive layer is then formed to conformably cover the inside surface of the storage node opening and on the third dielectric layer.

Abstract: The present invention proposes a method for fabricating shallow trench regions for isolation. A masking oxide layer is patterning on a semiconductor substrate, and the active areas are defined by recessing the semiconductor substrate to form trench regions. Silicon spacers are then formed on the sidewalls of the trench regions by LPCVD of amorphous silicon followed by an anisotropic etching. Sub-trench regions are thus constructed with the silicon spacers as its sidewalls. An ion implantation is performed to form channel stop regions. A thermal oxidation is carried out to grow a thermal oxide layer on the sidewalls and bottoms of the trench regions. A thick CVD oxide layer is deposited on the semiconductor substrate, and the oxide film outside the trench regions is removed by using a CMP process.

Abstract: In the preferred embodiment for forming a ragged polysilicon crown-shaped capacitor of a dynamic random access memory cell, a first dielectric layer is formed on a semiconductor substrate. A portion of the first dielectric layer is removed to define a contact hole within the first dielectric layer, wherein the contact hole is extended down to a source region in the substrate. Next, a conductive plug is formed and communicated to the source region within the contact hole. A second dielectric layer is formed on the first dielectric layer and the conductive plug, and a third dielectric layer is formed on the second dielectric layer. Next, portions of the third dielectric layer and the second dielectric layer are removed to define a storage node opening, wherein the storage node opening is located over the conductive plug. A first conductive layer is then formed to conformably cover the inside surface of the storage node opening and on the third dielectric layer.