Abstract: A high voltage vertical field effect transistor device (101) is fabricated in a substrate (102, 104) using angled implantations (116, 120) into trench sidewalls formed above recessed gate poly layers (114) to form self-aligned N+ regions (123) adjacent to the trenches and along an upper region of an elevated substrate. With a trench fill insulator layer (124) formed over the recessed gate poly layers (114), self-aligned P+ body contact regions (128) are implanted into the elevated substrate without counter-doping the self-aligned N+ regions (123), and a subsequent recess etch removes the elevated substrate, leaving self-aligned N+ source regions (135-142) and P+ body contact regions (130-134).

Abstract: Embodiments of semiconductor devices and methods of their formation include providing a semiconductor substrate having a top surface, a bottom surface, an active region, and an edge region, and forming a gate structure in a first trench in the active region of the semiconductor substrate. A termination structure is formed in a second trench in the edge region of the semiconductor substrate. The termination structure has an active region facing side and a device perimeter facing side. The method further includes forming first and second source regions of the first conductivity type are formed in the semiconductor substrate adjacent both sides of the gate structure. A third source region is formed in the semiconductor substrate adjacent the active region facing side of the termination structure. The semiconductor device may be a trench metal oxide semiconductor device, for example.

Abstract: A power MOSFET includes a semiconductor substrate with an upper surface, a cavity of a first depth in the substrate whose sidewall extends to the upper surface, a dielectric liner in the cavity, a gate conductor within the dielectric liner extending to or above the upper surface, body region(s) within the substrate of a second depth, separated from the gate conductor in a lower cavity region by first portion(s) of the dielectric liner of a first thickness, and source region(s) within the body region(s) extending to a third depth that is less than the second depth. The source region(s) are separated from the gate conductor by a second portion of the dielectric liner of a second thickness at least in part greater than the first thickness. The dielectric liner has a protrusion extending laterally into the gate conductor away from the body region(s) at or less than the third depth.

Abstract: Field effect devices and ICs with very low gate-drain capacitance Cgd are provided by forming a substantially empty void between the gate and the drain regions. For vertical FETS a cavity is etched in the semiconductor (SC) and provided with a gate dielectric liner. A poly-SC gate deposited in the cavity has a central fissure (empty pipe) extending through to the underlying SC. This fissure is used to etch the void in the SC beneath the poly-gate. The fissure is then closed by a dielectric plug formed by deposition or oxidation without significantly filling the etched void. Conventional process steps are used to provide the source and body regions around the cavity containing the gate, and to provide a drift space and drain region below the body region. The etched void between the gate and drain provides lower Cgd and Ron*Qg than can be achieved using low k dielectrics.

Abstract: A method is used to form a vertical MOS transistor. The method utilizes a semiconductor layer. An opening is etched in the semiconductor layer. A gate dielectric is formed in the opening that has a vertical portion that extends to a top surface of the first semiconductor layer. A gate is formed in the opening having a major portion laterally adjacent to the vertical portion of the gate dielectric and an overhang portion that extends laterally over the vertical portion of the gate dielectric. An implant is performed to form a source region at the top surface of the semiconductor layer while the overhang portion is present.

Abstract: A method is used to form a vertical MOS transistor. The method utilizes a semiconductor layer. An opening is etched in the semiconductor layer. A gate dielectric is formed in the opening that has a vertical portion that extends to a top surface of the first semiconductor layer. A gate is formed in the opening having a major portion laterally adjacent to the vertical portion of the gate dielectric and an overhang portion that extends laterally over the vertical portion of the gate dielectric. An implant is performed to form a source region at the top surface of the semiconductor layer while the overhang portion is present.

Abstract: A TMOS device (10) is formed using a semiconductor layer (16) of a first type. First and second regions (62,64) of the second type are formed in the semiconductor layer and are spaced apart. A third region (68) is formed in the semiconductor layer by implanting. The third region is between and contacts the first and second doped regions, is of the second conductivity type, and is less heavily doped than the first and second doped regions. A gate stack (67) is formed over a portion of the first doped region, a portion of the second doped region, and the third doped region. By implanting after forming the gate stack, fourth and fifth regions (98,100) of the first type are formed in interior portions of the first and second doped regions, respectively. The third region being of the same conductivity type as the first and second regions reduces Miller capacitance.

Abstract: Embodiments of a semiconductor device include a semiconductor substrate having a first surface and a second surface opposed to the first surface, a trench formed in the semiconductor substrate and extending from the first surface partially through the semiconductor substrate, a gate electrode material deposited in the trench, and a void cavity in the semiconductor substrate between the gate electrode material and the second surface. A portion of the semiconductor substrate is located between the void cavity and the second surface.

Abstract: Embodiments of a method for fabricating a semiconductor device having a reduced gate-drain capacitance are provided. In one embodiment, the method includes the steps of etching a trench in a semiconductor substrate utilizing an etch mask, widening the trench to define overhanging regions of the etch mask extending partially over the trench, and depositing a gate electrode material into the trench and onto the overhanging regions. The gate electrode material merges between the overhanging regions prior to the filling of the trench to create an empty fissure within the trench. A portion of the semiconductor substrate is removed through the empty fissure to form a void cavity proximate the trench.

Abstract: Field effect devices and ICs with very low gate-drain capacitance Cgd are provided by forming a substantially empty void between the gate and the drain regions. For vertical FETS a cavity is etched in the semiconductor (SC) and provided with a gate dielectric liner. A poly-SC gate deposited in the cavity has a central fissure (empty pipe) extending through to the underlying SC. This fissure is used to etch the void in the SC beneath the poly-gate. The fissure is then closed by a dielectric plug formed by deposition or oxidation without significantly filling the etched void. Conventional process steps are used to provide the source and body regions around the cavity containing the gate, and to provide a drift space and drain region below the body region. The etched void between the gate and drain provides lower Cgd and Ron*Qg than can be achieved using low k dielectrics.

Abstract: Embodiments of a method for fabricating a semiconductor device having a reduced gate-drain capacitance are provided. In one embodiment, the method includes the steps of etching a trench in a semiconductor substrate utilizing an etch mask, widening the trench to define overhanging regions of the etch mask extending partially over the trench, and depositing a gate electrode material into the trench and onto the overhanging regions. The gate electrode material merges between the overhanging regions prior to the filling of the trench to create an empty fissure within the trench. A portion of the semiconductor substrate is removed through the empty fissure to form a void cavity proximate the trench.

Abstract: Semiconductor structures (52-9, 52-11, 52-12) and methods (100-300) are provided for a semiconductor devices employing strained (70) and relaxed (66) semiconductors, The method comprises, forming (106, 208, 308) on a substrate (54, 56, 58) first (66-1) and second (66-2) regions of a first semiconductor material (66) of a first conductivity type and a first lattice constant spaced apart by a gap or trench (69), filling (108, 210, 308) the trench or gap (69) with a second semiconductor material (70) of a second, conductivity type and a second different lattice constant so that the second semiconductor material (70) is strained with respect to the first semiconductor material (66) and forming (110, 212, 312) device regions (80, 88, S, G, D) communicating with the first (66) and second (70) semiconductor materials and adapted to provide device current (87, 87?) through at least part of the strained second semiconductor material (70) in the trench (69).

Abstract: Methods for forming semiconductor structures are provided for a semiconductor device employing a superjunction structure and overlying trench with embedded control gate. An embodiment comprises forming interleaved first and second spaced-apart regions of first and second semiconductor materials of different conductivity type and different mobilities so that the second semiconductor material has a higher mobility for the same carrier type than the first semiconductor material, and providing an overlying third semiconductor material in which a trench is formed with sidewalls having thereon a fourth semiconductor material that has a higher mobility than the third material, adapted to carry current between source regions, through the fourth semiconductor material in the trench and the second semiconductor material in the device drift space to the drain.

Abstract: Semiconductor structures and methods are provided for a semiconductor device (40) employing a superjunction structure (41) and overlying trench (91) with embedded control gate (48). The method comprises, forming (52-6, 52-9) interleaved first (70-1, 70-2, 70-3, 70-4, etc.) and second (74-1, 74-2, 74-3, etc.

Abstract: Means and methods are provided for trench TMOS devices (41-10, 11, 12), comprising, providing a first semiconductor (53, 53?) of a first composition having an upper surface (541), with a body portion (54) proximate the upper surface (541), a drift portion (46, 83) spaced apart from the upper surface (541) and a trench (49, 49?) having sidewalls (493) extending from the upper surface (541) into the drift portion (46, 83). A second semiconductor (56) adapted to provide a higher mobility layer is applied on the trench sidewalls (493) where parts (78) of the body portion (54) are exposed. A dielectric (70) covers the higher mobility layer (56) and separates it from a control gate (72) in the trench (49, 49?). Source regions (68) formed in the body portion (54) proximate the upper surface (491) communicate with the higher mobility layer (56).

Abstract: A TMOS device (10) is formed using a semiconductor layer (16) of a first type. First and second regions (62,64) of the second type are formed in the semiconductor layer and are spaced apart. A third region (68) is formed in the semiconductor layer by implanting. The third region is between and contacts the first and second doped regions, is of the second conductivity type, and is less heavily doped than the first and second doped regions. A gate stack (67) is formed over a portion of the first doped region, a portion of the second doped region, and the third doped region. By implanting after forming the gate stack, fourth and fifth regions (98,100) of the first type are formed in interior portions of the first and second doped regions, respectively. The third region being of the same conductivity type as the first and second regions reduces Miller capacitance.

Abstract: Semiconductor structures and methods are provided for a semiconductor device (54-11, 54-12) employing a superjunction structure (81). The method comprises, forming (52-6) first spaced-apart regions (70-1, 70-2, 70-3, 70-4, etc.) of a first semiconductor material (70) of a first conductivity type, forming (52-9) second spaced-apart regions (74-1, 74-2, 74-3, etc.) of a second semiconductor material (74) of opposite conductivity type interleaved with the first space-apart regions (70-1, 70-2, 70-3, 70-4, etc.) with PN junctions therebetween, thereby forming a superjunction structure, wherein the second regions have higher mobility than the first regions for the same carrier type. Other regions (88) are provided in contact with the superjunction structure (81) to direct control current flow therethrough. In a preferred embodiment, the first material (70) is relaxed SiGe and the second material (74) is strained silicon.

Abstract: Methods and apparatus are provided for TMOS devices, comprising multiple N-type source regions, electrically in parallel, located in multiple P-body regions separated by N-type JFET regions at a first surface. The gate overlies the body channel regions and the JFET region lying between the body regions. The JFET region communicates with an underlying drain region via an N-epi region. Ion implantation and heat treatment are used to tailor the net active doping concentration Nd in the JFET region of length Lacc and net active doping concentration Na in the P-body regions of length Lbody so that a charge balance relationship (Lbody*Na)=k1*(Lacc*Nd) between P-body and JFET regions is satisfied, where k1 is about 0.6?k1?1.4. The entire device can be fabricated using planar technology and the charge balanced regions need not extend through the underlying N-epi region to the drain.

Abstract: Semiconductor structures and methods are provided for a semiconductor device (54-11, 54-12) employing a superjunction structure (81). The method comprises, forming (52-6) first spaced-apart regions (70-1, 70-2, 70-3, 70-4, etc.) of a first semiconductor material (70) of a first conductivity type, forming (52-9) second spaced-apart regions (74-1, 74-2, 74-3, etc.) of a second semiconductor material (74) of opposite conductivity type interleaved with the first space-apart regions (70-1, 70-2, 70-3, 70-4, etc.) with PN junctions therebetween, thereby forming a superjunction structure, wherein the second regions have higher mobility than the first regions for the same carrier type. Other regions (88) are provided in contact with the superjunction structure (81) to direct control current flow therethrough. In a preferred embodiment, the first material (70) is relaxed SiGe and the second material (74) is strained silicon.

Abstract: Semiconductor structures and methods are provided for a semiconductor device (40) employing a superjunction structure (41) and overlying trench (91) with embedded control gate (48). The method comprises, forming (52-6, 52-9) interleaved first (70-1, 70-2, 70-3, 70-4, etc.) and second (74-1, 74-2, 74-3, etc.