发明名称 |
Silicon waveguide on bulk silicon substrate and methods of forming |
摘要 |
Various methods include: forming a first set of trenches in a precursor structure having: a silicon substrate having a crystal direction, the silicon substrate substantially abutted by a first oxide; a silicon germanium (SiGe) layer overlying the silicon substrate; a silicon layer overlying the SiGe layer; a second oxide overlying the silicon layer; and a sacrificial layer overlying the second oxide, wherein the first set of trenches each expose the silicon substrate and internal sidewalls of the first oxide; undercut etching the silicon substrate in a direction perpendicular to the crystal direction of the silicon substrate to form a cavity corresponding with each of the first set of trenches; and partially filling each cavity with a dielectric, leaving an air gap within each cavity connected with an air gap in an adjacent cavity. |
申请公布号 |
US9059252(B1) |
申请公布日期 |
2015.06.16 |
申请号 |
US201414176552 |
申请日期 |
2014.02.10 |
申请人 |
International Business Machines Corporation |
发明人 |
Liu Qizhi;Shank Steven M. |
分类号 |
H01L21/8236;H01L21/336;H01L21/768 |
主分类号 |
H01L21/8236 |
代理机构 |
Hoffman Warnick LLC |
代理人 |
LeStrange Michael J.;Hoffman Warnick LLC |
主权项 |
1. A method comprising:
forming a first set of trenches in a precursor structure having:
a silicon substrate having a crystal direction, the silicon substrate substantially abutted by a first oxide;a silicon germanium (SiGe) layer overlying the silicon substrate;a silicon layer overlying the SiGe layer;a second oxide overlying the silicon layer; anda sacrificial layer overlying the second oxide, wherein the first set of trenches each expose the silicon substrate and internal sidewalls of the first oxide; undercut etching the silicon substrate in a direction perpendicular to the crystal direction of the silicon substrate to form a cavity corresponding with each of the first set of trenches; and at least partially filling each cavity with a dielectric, leaving an air gap within each cavity connected with an air gap in an adjacent cavity. |
地址 |
Armonk NY US |