Abstract: The a trench semiconductor device such as a power MOSFET the high electric field at the corner of the trench is diminished by increasing the thickness of the gate oxide layer at the bottom of the trench. Several processes for manufacturing such devices are described. In one group of processes a directional deposition of silicon oxide is performed after the trench has been etched, yielding a thick oxide layer at the bottom of the trench. Any oxide which deposits on the walls of the trench is removed before a thin gate oxide layer is grown on the walls. The trench is then filled with polysilicon in or more stages. In a variation of the process a small amount of photoresist is deposited on the oxide at the bottom of the trench before the walls of the trench are etched. Alternatively, polysilicon can be deposited in the trench and etched back until only a portion remains at the bottom of the trench. The polysilicon is then oxidized and the trench is refilled with polysilicon.

Abstract: A power MISFET, which has a desired gate breakdown voltage, can be manufactured will controlling an increase in parasitic capacitance. After depositing a polycrystalline silicon film on a substrate and embedding groove portions in the polycrystalline silicon film by patterning the polycrystalline silicon film in an active cell area, a gate electrode is formed within the groove portion, and the inside of the groove portion is embedded in a gate wiring area. Extending to the outside of the groove portion continuously out of the groove portion, there is a gate drawing electrode electrically connected to the gate electrode. Slits extending from the end portion of the gate drawing electrode are formed in the gate drawing electrode outside of the groove portion. Then, a silicon oxide film and a BPSG film are deposited on the substrate.

Abstract: Consistent with an example embodiment a trench-gate semiconductor device, for example a MOSFET or IGBT, having a field plate provided below the trenched gate is manufactured using a process with improved reproducibility. The process includes the steps of etching a first grove into the semiconductor body for receiving the gate, and etching a second groove into the top major surface of the semiconductor body, the second groove extending from the first groove and being narrower than the first groove. The invention enables better control of the vertical extent of the gate below the top major surface of the semiconductor body.

Abstract: Described is a method for fabricating a semiconductor device having an FET of a trench-gate structure obtained by disposing a conductive layer, which will be a gate, in a trench extended in the main surface of a semiconductor substrate, wherein the upper surface of the trench-gate conductive layer is formed higher than the main surface of the semiconductor substrate and the trench gate conductive layer and gate insulating film are formed in the trench and over the main surface of the semiconductor substrate at the periphery of the trench.

Abstract: The present invention relates to a manufacturing method for a recessed channel array transistor and a corresponding recessed channel array transistor. In one embodiment, the present invention uses a self-adjusting spacer on the substrate surface to provide the required distance between the gate and the source/drain regions. Thus, the requirements regarding the tolerances of the lithography in the gate contact plane are diminished.

Abstract: When fabricating trench power transistor arrangements (1) with active cell array trenches (5) and passive connecting trenches (6), the cell array trenches (5) are provided in greater width than the connecting trenches (6). An auxiliary layer (24) is deposited conformally onto a lower field electrode structure (11) in the cell array trenches (5) and the connecting trenches (6) and is etched back as far as the top edge in the connecting trenches (6), which removes it from the cell array trenches (5). The auxiliary layer (24) allows the gate oxide (20) to be patterned without a complex mask process. An edge trench (7), with an electrode, on the potential of the field electrode structure (11) shields the cell array (3) from a drain potential.

Abstract: A method of forming a channel region for a MOSFET device in a strained silicon layer via employment of adjacent and surrounding silicon-germanium shapes, has been developed. The method features simultaneous formation of recesses in a top portion of a conductive gate structure and in portions of the semiconductor substrate not occupied by the gate structure or by dummy spacers located on the sides of the conductive gate structure. The selectively defined recesses will be used to subsequently accommodate silicon-germanium shapes, with the silicon-germanium shapes located in the recesses in the semiconductor substrate inducing the desired strained channel region. The recessing of the conductive gate structure and of semiconductor substrate portions reduces the risk of silicon-germanium bridging across the surface of sidewall spacers during epitaxial growth of the alloy layer, thus reducing the risk of gate to substrate leakage or shorts.

Abstract: A method of integrating a non-MOS transistor device and a CMOS electronic device on a semiconductor substrate includes forming openings within an active semiconductor layer in first and second regions of a semiconductor substrate. The first region corresponds to a non-MOS transistor device portion and the second region corresponds to a CMOS electronic device portion. The openings are formed using a dual trench process, forming openings or shallow trenches in the non-MOS transistor device portion to a first depth, and openings in the CMOS electronic device portion to a second depth greater than the first depth.

Abstract: A semiconductor device having a recess gate is formed by first forming a recess below the upper surface of the substrate. A spacer is formed at each sidewall of the recess. An impurity doping area is formed in a source area. A first LDD area is formed in a drain area. A gate comprising a gate insulating layer and a gate conductive layer is then formed in the recess. A second LDD area is formed on the upper surface of the semiconductor substrate. A gate spacer is formed at each sidewall of the gate. Then a source/drain area having an asymmetrical structure is formed on each side of the gate.

Abstract: In a method of manufacturing a vertical MOS transistor, a body region, a trench, a gate oxide film, a gate electrode, a source region, and a body contact region are successively formed in a semiconductor substrate. An intermediate insulating film is deposited over a main surface of the semiconductor substrate and the gate electrode. The intermediate insulating film overlying the main surface of the semiconductor substrate is then etched back so as to entirely expose the source region and the body contact region. A source metal electrode is formed over the main surface of the semiconductor substrate so as to cover the source region and body contact region.

Abstract: Recessed gate transistor structures and methods for making the same prevent a short between a gate conductive layer formed on a non-active region and an active region by forming an insulation layer therebetween, even though a misalignment is generated in forming a gate. The method and structure reduce the capacitance between gates. The method includes forming a device isolation film for defining an active region and a non-active region, on a predetermined region of a semiconductor substrate. First and second insulation layers are formed on an entire face of the substrate. A recess is formed in a portion of the active region. A gate insulation layer is formed within the recess, and then a first gate conductive layer is formed within the recess. A second gate conductive layer is formed on the second insulation layer and the first gate conductive layer. Subsequently, source/drain regions are formed.

Abstract: To reduce the on-resistance in a semiconductor device, such as a trench lateral power MOSFET, a trench etching region forms a mesh pattern in which a first trench section, formed in an active region, and a second trench section, formed in a gate region for leading out gate polysilicon to a substrate surface, intersect each other. An island-like non-trench region, which is left without being subjected to etching, is divided into a plurality of smaller regions by one or more third trench section that connect with the first and second trench sections that form the mesh pattern. In each non-trench region, a contact section for connecting a drain region (or a source region) and an electrode is formed so as to be spread over all of the smaller regions in the non-trench region.

Abstract: A gate structure for a semiconductor device includes a shielding electrode and a switching electrode. Respective portions of the shielding electrode are disposed above said drain region and said well region. A first dielectric layer is disposed between the shielding electrode and the drain and well regions. The switching electrode includes respective portions that are disposed above said well region and said source region. A second dielectric layer is disposed between the switching electrode and the well and source regions. A third dielectric layer is disposed between the shielding electrode and the switching electrode.