Optical semiconductor device and method for making the device

Patent metadata

Field	Value
Publication number	US-2016284929-A1
Application number	US-201615076427-A
Country	US
Kind code	A1
Filing date	Mar 21, 2016
Priority date	Mar 26, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

An optical semiconductor device comprises, on a substrate, a fin of diamond-cubic semiconductor material and, at the base of the fin, a slab of that semiconductor material, in a diamond-hexagonal structure, that extends over the full width of the fin, the slab being configured as an optically active material. This semiconductor material can contain silicon. A method for manufacturing the optical semiconductor device comprises annealing the sidewalls of the fin, thereby inducing a stress gradient along the width of the fin.

First claim

What is claimed is:

1 . A method for manufacturing an optical semiconductor device, comprising:
providing a substrate comprising a layer of semiconductor material, wherein the semiconductor material has a diamond-cubic structure; patterning the layer of semiconductor material having the diamond-cubic structure to form a fin sandwiched between a first confined space and a second confined space, the first confined space being adjacent to a first major sidewall of the fin and the second confined space being adjacent to a second major sidewall of the fin, whereby the first confined space and the second confined space comprise an oxide material in contact with the first major sidewall and the second major sidewall, wherein the first confined space is smaller than the second confined space; and annealing the substrate, thereby forming at the base of the fin and across a full width of the fin a slab of semiconductor material having a diamond-hexagonal structure.

2 . The method of claim 1 , wherein at least one of the first confined space and the second confined space is confined by the fin and another major sidewall of another fin.

3 . The method of claim 2 , wherein the another fin is patterned together with the fin.

4 . The method of claim 3 , wherein a width of the confined spaces between fins gradually increases along an array of fins.

5 . The method of claim 1 , wherein annealing the substrate comprises oxidizing the first major sidewall and the second major sidewall.

6 . The method of claim 5 , wherein oxidizing comprises wet oxidation.

7 . The method of claim 1 , wherein the first confined space is covered with a capping layer, the capping layer configured as a diffusion barrier for oxygen.

8 . The method of claim 1 , wherein the semiconductor material is selected from the group consisting of Si and Si x Ge 1 , wherein 0<x<1.

9 . The method of claim 1 , wherein a width at the base of the fin is smaller than 50 nm.

10 . An optical semiconductor device comprising:
a fin on a substrate, wherein the fin comprises a semiconductor material selected from the group consisting of Si and Si x Ge 1-x wherein 0<x<1, and wherein the semiconductor material of the fin has a diamond-cubic structure; and a slab of semiconductor material selected from the group consisting of Si and Si x Ge 1-x wherein 0<x<1, wherein the semiconductor material of the slab has a diamond-hexagonal structure, wherein the slab is situated across a full width of the fin at a base of the fin; wherein the fin is sandwiched in between a first confined space and a second confined space, wherein a width of first confined space is smaller than a width the second confined space.

11 . The optical semiconductor device of claim 11 , wherein the fin comprises a step at a side of the first confined space and a bulge at a side of the second confined space, wherein the step is adjacent to the slab.

12 . The optical semiconductor device of claim 11 , wherein the slab has a thickness of from 2 nm to 50 nm.

Assignees

• Imec Vzw

Inventors

• Bender Hugo
• Qiu Yang

Classifications

• H10P14/2926

  Crystal orientations · CPC title

• H10P14/2905

  Silicon, silicon germanium or germanium · CPC title

• H10W10/0143

  comprising concurrently refilling multiple trenches having different shapes or dimensions · CPC title

• H10W10/17

  formed using trench refilling with dielectric materials, e.g. shallow trench isolations · CPC title

• H10W10/014

  using trench refilling with dielectric materials, e.g. shallow trench isolations · CPC title