Abstract: A device termination structure, and/or a gate bus-bar structure, and/or other end structure is provided for at least one group of cells in a cellular trench-gate semiconductor device, for example a power MOSFET. In this end structure, a conductive layer (11c), for example of polysilicon gate material, extends on an intermediate insulating layer (55) over a higher-doped (P+) end region (150) of the channel-accommodating region (15). This insulating layer (55) comprises an area (51e) of a trench-etch mask (51), preferably comprising silicon nitride, that is of greater thickness than the gate dielectric layer (17). A window (51a) extends through the trench-etch mask (51) at a location where an end trench (20e) extends into the P+ region (150). The end trench (20e) is an extension of the insulated gate trench (20) into the P+ region (150) and accommodates an extension (11e) of the trench-gate (11). The conductive layer (11c) is connected to the trench-gate extension (11e) via the window (51e).

Abstract: A device termination structure, and/or a gate bus-bar structure, and/or other end structure is provided for at least one group of cells in a cellular trench-gate semiconductor device, for example a power MOSFET. In this end structure, a conductive layer (11c), for example of polysilicon gate material, extends on an intermediate insulating layer (55) over a higher-doped (P+) end region (150) of the channel-accommodating region (15). This insulating layer (55) comprises an area (51e) of a trench-etch mask (51), preferably comprising silicon nitride, that is of greater thickness than the gate dielectric layer (17). A window (51a) extends through the trench-etch mask (51) at a location where an end trench (20e) extends into the P+ region (150). The end trench (20e) is an extension of the insulated gate trench (20) into the P+ region (150) and accommodates an extension (11e) of the trench-gate (11). The conductive layer (11c) is connected to the trench-gate extension (11e) via the window (51e).

Abstract: A device termination structure, and/or a gate bus-bar structure, and/or other end structure is provided for at least one group of cells in a cellular trench-gate semiconductor device, for example a power MOSFET. In this end structure, a conductive layer (11c), for example of polysilicon gate material, extends on an intermediate insulating layer (55) over a higher-doped (P+) end region (150) of the channel-accommodating region (15). This insulating layer (55) comprises an area (51e) of a trench-etch mask (51), preferably comprising silicon nitride, that is of greater thickness than the gate dielectric layer (17). A window (51a) extends through the trench-etch mask (51) at a location where an end trench (20e) extends into the P+ region (150). The end trench (20e) is an extension of the insulated gate trench (20) into the P+ region (150) and accommodates an extension (11e) of the trench-gate (11). The conductive layer (11c) is connected to the trench-gate extension (11e) via the window (51e).

Abstract: Compact trench-gate semiconductor devices, for example a cellular power MOSFET with sub-micron pitch (Yc), are manufactured with self-aligned techniques that use sidewall spacers (52) in different ways. Thereby, the source region (13) and a contact window (18a) for a source electrode (33) can be self-aligned to a narrow trench (20) containing the trench-gate (11). Thereby, the channel-accommodating region (15) can also be provided after forming the trench-gate (11), and with very good control of its doping concentration (Na; p) adjacent to the trench (20). To achieve this control, its dopant is provided after removing the spacers (52) from the mask (51) so as to form a doping window (51b), which may also be used for the source dopant, adjacent to the trench-gate (11). A high energy dopant implant (61) or other doping process provides this channel dopant adjacent to the trench (20) and extending laterally below the mask (51,51n).

Abstract: Compact trench-gate semiconductor devices, for example a cellular power MOSFET with sub-micron pitch (Yc), are manufactured with self-aligned techniques that use sidewall spacers (52) in different ways. The trench-gate (11) is accommodated in a narrow trench (20) that is etched via a narrow window (52b) defined by the spacers (52) at sidewalls of a wider window (51a) of a mask (51) at the body surface (10a). The spacers (52) permit a source region (13) adjacent to the trench-gate (11) and an insulating overlayer (18) over the trench-gate (11) to be self-aligned to this narrow trench (20). The overlayer (18), which defines a contact window (18a) for a source electrode (33), is provided in a simple but reproducible manner by deposition and etch-back, after removing the spacers (52). Its overlap (y4, y4′) with the body surface (10a) is well-defined, so reducing a short-circuit risk between the source electrode (33) and the trench-gate (11).

Abstract: A device termination structure, and/or a gate bus-bar structure, and/or other end structure is provided for at least one group of cells in a cellular trench-gate semiconductor device, for example a power MOSFET. In this end structure, a conductive layer (11c), for example of polysilicon gate material, extends on an intermediate insulating layer (55) over a higher-doped (P+) end region (150) of the channel-accommodating region (15). This insulating layer (55) comprises an area (51e) of a trench-etch mask (51), preferably comprising silicon nitride, that is of greater thickness than the gate dielectric layer (17). A window (51a) extends through the trench-etch mask (51) at a location where an end trench (20e) extends into the P+ region (150). The end trench (20e) is an extension of the insulated gate trench (20) into the P+ region (150) and accommodates an extension (11e) of the trench-gate (11). The conductive layer (11c) is connected to the trench-gate extension (11e) via the window (51e).

Abstract: Compact trench-gate semiconductor devices, for example a cellular power MOSFET with sub-micron pitch (Yc), are manufactured with self-aligned techniques that use sidewall spacers (52) in different ways. The trench-gate (11) is accommodated in a narrow trench (20) that is etched via a narrow window (52b) defined by the spacers (52) at sidewalls of a wider window (51a) of a mask (51) at the body surface (10a). The spacers (52) permit a source region (13) adjacent to the trench-gate (11) and an insulating overlayer (18) over the trench-gate (11) to be self-aligned to this narrow trench (20). The overlayer (18), which defines a contact window (18a) for a source electrode (33), is provided in a simple but reproducible manner by deposition and etch-back, after removing the spacers (52). Its overlap (y4, y4′) with the body surface (10a) is well-defined, so reducing a short-circuit risk between the source electrode (33) and the trench-gate (11).

Abstract: Compact trench-gate semiconductor devices, for example a cellular power MOSFET with sub-micron pitch (Yc), are manufactured with self-aligned techniques that use sidewall spacers (52) in different ways. Thereby, the source region (13) and a contact window (18a) for a source electrode (33) can be self-aligned to a narrow trench (20) containing the trench-gate (11). Thereby, the channel-accommodating region (15) can also be provided after forming the trench-gate (11), and with very good control of its doping concentration (Na; p) adjacent to the trench (20). To achieve this control, its dopant is provided after removing the spacers (52) from the mask (51) so as to form a doping window (51b), which may also be used for the source dopant, adjacent to the trench-gate (11). A high energy dopant implant (61) or other doping process provides this channel dopant adjacent to the trench (20) and extending laterally below the mask (51, 51n).