Implantation-less approach to fabricating strained semiconductor on isolation wafers
AssigneeChartered Semiconductor Manufacturing Ltd.
InventorsJinping Liu, Dong Sohn, Liang Hsia
Life of this patent
Estimating the term…
Abstract
A method of fabrication of semiconductor substrate structure comprising the following. A buffer layer is formed on the Si Substrate. We form a SiGe layer on the novel buffer layer. The buffer layer has defects therein so that the buffer layer is oxidized to form a buried isolation layer comprised of silicon oxide and an oxide layer and oxidize the SiGe layer for form a oxide layer. The oxide layer is then removed. An upper semiconductor layer (e.g., Si, SiGe or Ge layer) is epitaxially formed on the SiGe layer. Devices are formed on said an upper semiconductor layer. The buffer layer can be formed by several aspects.
Claims26
A method of fabrication of semiconductor substrate structure;
- comprising the steps of
- a) providing a substrate;
- b) forming a buffer layer on the substrate;
- c) forming a SiGe layer on the buffer layer;
- d) performing an oxidation processes to oxidize the buffer layer to form a buried isolation layer comprised of silicon oxide and an oxide layer and oxidize the SiGe layer for form a oxide layer;
- said oxide layer on top of said buffer layer.
A method of fabrication of semiconductor substrate structure;
- comprising the steps of:
- a) providing a substrate;
- (1) said substrate is preferably a p-type crystalline silicon substrate;
- b) a buffer layer is formed on the Si Substrate.
- (1) said buffer layer is comprised of between 1 and 5 composite layers;
- said composite layers are comprised of a lower silicon-Germanium-Carbon layer and a upper silicon-germanium layer;
- c) form a SiGe layer on the buffer layer;
- d) performing an oxidation processes to oxidize the buffer layer to form a buried isolation layer comprised of silicon oxide and an oxide layer and oxidize the SiGe layer for form a oxide layer;
- e) removing said oxide layer;
- f) forming an upper semiconductor layer over the SiGe layer.
The method of fabrication of semiconductor substrate structure;
- comprising the steps of:
- a) providing a substrate;
- (1) said substrate is preferably a p-type crystalline silicon substrate with a <100> crystallographic orientation.
- b) a buffer layer is formed on the Si Substrate.
- (1) said buffer layer is comprised of one or more SiGe alloy layers;
- said SiGe alloy layers are comprised of Si—Ge wherein said SiGe alloy layers have a varying Ge concentration in the thickness direction of said buffer layer, said Ge concentration having a first value at the interface with said substrate and having a second value at full thickness of said buffer layer, said first value of Ge concentration being larger than said second value of Ge concentration,
- c) form a SiGe layer on the buffer layer;
- d) performing an oxidation processes to oxidize the buffer layer to form a buried isolation layer comprised of silicon oxide and an oxide layer and oxidize the SiGe layer for form a oxide layer;
- e) removing said oxide layer;
- f) forming an upper semiconductor layer over the SiGe layer;
- g) forming devices on said upper semiconductor layer.
Dependencies are inferred from the claim text.