# US 2008/0185643 A1 · Semiconductor device having trench edge termination structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185643 A1 - Document ID: US20080185643A1 - Status: Published application - Kind: A1 - Application number: 11/671,514 - Filed: 2007-02-06 - Published: 2008-08-07 - Earliest claimed: 2007-02-06 - Assignees: Semiconductor Components Industries, LLC - Inventors: Zia Hossain - Web page: https://patentgrep.com/patent/US20080185643A1 ## CPC - H10D 30/665: {having edge termination structures} - H10D 30/66: Vertical DMOS [VDMOS] FETs - H10D 62/111: {Multiple RESURF structures, e.g. double RESURF or 3D-RESURF structures} - H10D 12/441: {Vertical IGBTs} - H10D 18/40: with turn-on by field effect - H10D 62/116: {adjoining the input or output regions of field-effect devices, e.g. adjoining source or drain regions} - H10D 62/127: {of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs} - H10D 64/252: {for vertical or pseudo-vertical devices} - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract In one embodiment, a device is formed in a region of semiconductor material. The device includes active cell trenches and termination trenches each having doped sidewall surfaces that compensate the region of semiconductor material during reverse bias conditions to form a superjunction structure. The termination trenches include a trench fill material that enhances depletion region spread during reverse bias conditions. ## Claims ### Claim 1 A superjunction semiconductor device comprising: a semiconductor substrate having a surface configured to form a first electrode; a region of semiconductor material formed in spaced relationship with the semiconductor substrate and having an active region and a termination region, the region of semiconductor material having a first conductivity type and a first charge density; an active device formed in the active region, wherein the active device comprises: first and second trenches formed in the region of semiconductor material, wherein the first and second trenches have sidewall surfaces; first doped regions of a second conductivity type opposite the first conductivity type formed along at least portions of the sidewall surfaces of the first and second trenches, wherein the first doped regions have a second charge density configured to balance the first charge density to form a superjunction structure; a base region of the second conductivity type formed in the region of semiconductor material between the first and second trenches; a source region of the first conductivity type formed in the base region; a first insulated control electrode adjacent the base region and the source region and configured to control current flow between the source region and the first electrode; and a first trench fill material formed within the first and second trenches; and a termination structure formed in the termination region, wherein the termination structure comprises: a plurality of termination trenches formed in the body of semiconductor material and extending to the semiconductor substrate, wherein each of the plurality of termination trenches has second doped regions of the second conductivity type formed along sidewall surfaces, wherein the second doped regions have the second charge density configured to balance the first charge density; a second trench fill material formed within the plurality of termination trenches; and an insulating layer formed overlying the termination structure and configured so that the second trench fill material within the plurality of termination trenches and the second doped regions are floating. ### Claim 2 (depends on 1) The device of claim 1, wherein the first and second trench fill materials comprises the same material. ### Claim 3 (depends on 1) The device of claim 1, wherein the first and second trench fill materials comprise different materials. ### Claim 4 (depends on 3) The device of claim 3, wherein the first trench fill material comprises a dielectric material, and wherein the second the trench fill material comprises a semiconductor material. ### Claim 5 (depends on 4) The device of claim 4, wherein the second trench fill material comprises a polycrystalline semiconductor material. ### Claim 6 (depends on 4) The device of claim 4, wherein the second trench fill material comprises a single crystal semiconductor material. ### Claim 7 (depends on 1) The device of claim 1, wherein each of the first doped regions and each of the second doped regions have substantially equivalent charge densities. ### Claim 8 (depends on 1) The device of claim 1, further comprising a field plate overlying the insulating layer and only a portion of the plurality of termination trenches. ### Claim 9 (depends on 1) The device of claim 1, wherein the second doped regions extend along an entire length of the sidewalls of the plurality of termination trenches. ### Claim 10 (depends on 1) The device of claim 1, wherein the first and second trenches comprise striped shaped trenches, and wherein the plurality of termination trenches comprise concentric rings laterally surrounding the first and second trenches. ### Claim 11 (depends on 1) The device of claim 1 further comprising a terminating junction of the second conductivity type formed in the body of semiconductor material between the second trench and an innermost termination trench. ### Claim 12 (depends on 11) The device of claim 11 further comprising a second insulated control electrode adjacent the termination junction, and wherein the termination junction is electrically coupled to the source region. ### Claim 13 (depends on 1) The device of claim 1, wherein an outer edge of an innermost termination trench is spaced apart from an inner edge of a second innermost termination trench a distance between about five micrometers and about nine micrometers, and wherein the innermost termination trench has a width between about two micrometers and five micrometers. ### Claim 14 A superjunction semiconductor device comprising: a semiconductor substrate having a surface configured to form a first electrode; a region of semiconductor material formed in spaced relationship with the semiconductor substrate and having an active region and a termination region, the region of semiconductor material having a first conductivity type and a first charge density; an active device formed in the active region, wherein the active device comprises: first and second trenches formed in the region of semiconductor material, wherein the first and second trenches have sidewall surfaces; first doped regions of a second conductivity type opposite the first conductivity type formed along at least portions of the sidewall surfaces of the first and second trenches, wherein the first doped regions have a second charge density configured to balance the first charge density to form a superjunction structure; a base region of the second conductivity type formed in the region of semiconductor material between the first and second trenches; a source region of the first conductivity type formed in the base region; a first insulated control electrode adjacent the base region and the source region and configured to control current flow between the source region and the first electrode; and a first trench fill material formed within the first and second trenches, wherein the first trench fill material comprises a dielectric material; and a termination structure formed in the termination region, wherein the termination structure comprises: a plurality of termination trenches formed in the body of semiconductor material and extending to the semiconductor substrate, wherein each of the plurality of termination trenches has second doped regions of the second conductivity type formed along sidewall surfaces, wherein the second doped regions have the second charge density configured to balance the first charge density; a second trench fill material formed within the plurality of termination trenches, wherein the second trench fill material comprises a semiconductor material; and an insulating layer formed overlying the termination structure and configured so that the second trench fill material within plurality of termination trenches and the second doped regions are floating. ### Claim 15 (depends on 14) The device of claim 14 further comprising a terminating junction of the second conductivity type formed in the body of semiconductor material between the second trench and an innermost termination trench. ### Claim 16 (depends on 15) The device of claim 15 further comprising a second insulated control electrode adjacent the termination junction, and wherein the termination junction is electrically coupled to the source region. ### Claim 17 (depends on 14) The device of claim 14, wherein the second trench fill material comprises a lightly doped semiconductor material having a dopant concentration between about two to about three orders of magnitude less than that of the region of semiconductor material. ### Claim 18 A superjunction semiconductor device comprising: a semiconductor substrate having a surface configured to form a first electrode; a region of semiconductor material formed in spaced relationship with the semiconductor substrate and having an active region and a termination region, the region of semiconductor material having a first conductivity type and a first charge density; an active device formed in the active region, wherein the active device comprises: first and second trenches formed in the region of semiconductor material, wherein the first and second trenches have sidewall surfaces; first doped regions of a second conductivity type opposite the first conductivity type formed along at least portions of the sidewall surfaces of the first and second trenches, wherein the first doped regions have a second charge density configured to balance the first charge density to form a superjunction structure; a base region of the second conductivity type formed in the region of semiconductor material between the first and second trenches; a source region of the first conductivity type formed in the base region; a first insulated control electrode adjacent the base region and the source region and configured to control current flow between the source region and the first electrode; and a first trench fill material formed within the first and second trenches; and a termination structure formed in the termination region, wherein the termination structure comprises: a plurality of termination trenches formed in the body of semiconductor material and extending to the semiconductor substrate, wherein each of the plurality of termination trenches is continuous and each has second doped regions of the second conductivity type formed along sidewall surfaces, wherein the second doped regions have the second charge density configured to balance the first charge density; a second trench fill material formed within the plurality of termination trenches, wherein the second trench fill material comprises single crystal semiconductor material; and an insulating layer formed overlying the termination structure and configured so that the second trench fill material within plurality of termination trenches and the second doped regions are floating. ### Claim 19 (depends on 18) The device of claim 18 further comprising: a terminating junction of the second conductivity type formed in the body of semiconductor material between the second trench and an innermost termination trench; and a second insulated control electrode adjacent the termination junction, and wherein the termination junction is electrically coupled to the source region. ### Claim 20 (depends on 18) The device of claim 18, wherein the semiconductor substrate comprises the first conductivity type.