US 2015/0084128 A1 · SEMICONDUCTOR-ON-INSULATOR (SOI) STRUCTURES WITH LOCAL HEAT DISSIPATER(S) AND METHODS

Abstract

Disclosed are semiconductor-on-insulator (SOI) structures comprising an SOI device (e.g., an SOI metal oxide semiconductor field effect transistor (MOSFET)) with local heat dissipater(s). Each heat dissipater comprises an opening, which is adjacent an active region of the SOI device, which extends through the insulator layer on which the SOI device sits to the semiconductor substrate below, and which is at least partially filled with a fill material. This fill material is a thermal conductor so as to dissipate heat generated by the SOI device and is also an electrical isolator so as to minimize current leakage. In the case of MOSFET, the local heat dissipater(s) can be aligned below the source/drain extension(s) or the source/drain(s). Alternatively, the local heat dissipater(s) can be aligned below the channel or parallel and adjacent to opposing sides of the channel. Also disclosed herein are methods of forming these SOI structures.

Claims22

Dependent claims

A semiconductor-on-insulator (SOI) structure comprising:

a semiconductor substrate;
an insulator layer on and immediately adjacent to said semiconductor substrate;
a semiconductor layer on and immediately adjacent to said insulator layer, said semiconductor layer comprising an active region of a semiconductor device;
and
a local heat dissipater comprising:
an opening extending vertically through said insulator layer from said semiconductor layer to said semiconductor substrate, said opening being aligned below said active region;
and
a fill material filling said opening so as to be immediately adjacent to said active region in said semiconductor layer and further so as to be immediately adjacent to said semiconductor substrate,
said fill material comprising an electrically insulative material such that said fill material and said insulator layer electrically isolate said semiconductor layer from said semiconductor substrate, and
said fill material being more thermally conductive than said insulator layer such that said fill material dissipates heat from said active region into said semiconductor substrate.

7 more elements

A method of forming a semiconductor-on-insulator (SOI) structure, said method comprising:

forming an insulator layer on and immediately adjacent to a semiconductor substrate;
forming a local heat dissipater in said insulator layer, said forming of said local heat dissipater comprising:
forming an opening extending vertically through said insulator layer to said semiconductor substrate;
depositing a fill material in said opening such that said fill material is immediately adjacent to said semiconductor substrate;
after said forming of said local heat dissipater, forming a semiconductor layer on and immediately adjacent to said insulator layer and said fill material within said opening;
and
forming a semiconductor device having an active region in said semiconductor layer, said active region being aligned above and immediately adjacent to said local heat dissipater,
said fill material comprising an electrically insulative material such that said fill material and said insulator layer electrically isolate said semiconductor layer from said semiconductor substrate, and
said fill material further being more thermally conductive than said insulator layer such that said fill material dissipates heat from said active region into said semiconductor substrate.

6 more elements

A method of forming a semiconductor-on-insulator (SOI) structure, said method comprising:

providing a semiconductor-on-insulator wafer comprising:
a semiconductor substrate;
an insulator layer on and immediately adjacent to said semiconductor substrate;
and
a semiconductor layer on and immediately adjacent to said insulator layer;
forming a local heat dissipater, said forming of said local heat dissipater comprising:
forming an opening extending vertically through said semiconductor layer and said insulator layer to said semiconductor substrate;
depositing a fill material into said opening immediately adjacent to said semiconductor substrate;
etching back said fill material to at least level with a top surface of said insulator layer;
and
depositing additional semiconductor material within said opening on said fill material;
and
any one of before said forming of said local heat dissipater and after said forming of said local heat dissipater, forming a semiconductor device having an active region in said semiconductor layer such that, within said semiconductor-on-insulator (SOI) structure, said local heat dissipater is aligned below and immediately adjacent to said active region,
said fill material comprising an electrically insulative material such that said fill material and said insulator layer electrically isolate said semiconductor layer and said additional semiconductor material from said semiconductor substrate, and
said fill material further being more thermally conductive than said insulator layer such that said fill material dissipates heat from said active region into said semiconductor substrate.

12 more elements

A method of forming a semiconductor-on-insulator (SOI) structure, said method comprising:

providing a semiconductor-on-insulator wafer comprising:
a semiconductor substrate;
an insulator layer on and immediately adjacent to said semiconductor substrate;
and
a semiconductor layer on and immediately adjacent to said insulator layer;
forming a shallow trench isolation region extending vertically through said semiconductor layer to said insulator layer and defining an active region for a semiconductor device within said semiconductor layer;
forming at least one local heat dissipater, said forming of said at least one local heat dissipater comprising:
forming, on opposing sides of said active region, openings extending vertically through said shallow trench isolation region and said insulator layer to said semiconductor substrate;
and
depositing a fill material in said openings such that said fill material is immediately adjacent to said semiconductor substrate;
and
etching said fill material to a level between a top surface and a bottom surface of said shallow trench isolation region such that at least an upper portion of said fill material in each of said openings is positioned laterally adjacent to said active region,
said fill material comprising an electrically insulative material such that said shallow trench isolation region, said fill material and said insulator layer electrically isolate said semiconductor layer from said semiconductor substrate, and
said fill material further being more thermally conductive than said shallow trench isolation region and said insulator layer such that said fill material dissipates heat from said active region into said semiconductor substrate.

11 more elements

Dependencies are inferred from the claim text.

Semiconductor-on-insulator (soi) structures with local heat dissipater(s) and methods

Life of this patent

Semiconductor-on-insulator (soi) structures with local heat dissipater(s) and methods

Life of this patent

Abstract

Claims22