Utilization of angled trench for effective aspect ratio trapping of defects in strain-relaxed heteroepitaxy of semiconductor films

A method for forming a semiconductor device, comprising:

• forming a non-crystalline layer over a first crystalline material;
• forming an angled trench through the non-crystalline layer to expose a portion of the first crystalline material at a bottom of the angled trench;
• and
• forming a second crystalline material from the bottom of the angled trench by epitaxial growth to fill the angled trench, wherein the first and second crystalline materials have mismatched lattice dimensions.

A method for forming a semiconductor device, comprising:

• forming a dielectric layer over a silicon containing crystalline substrate;
• forming an angled trench through the dielectric material to expose a portion of the silicon containing crystalline substrate at a bottom of the angled trench, wherein an angle between sidewalls of the angled trench and a top surface of the silicon containing crystalline substrate is less than
• tan
• -
• 1
• 
• h
• w
• ,
• h represents a thickness of the dielectric layer, and w represents a width of the angled trench along the top surface of the silicon containing crystalline substrate;
• etching the exposed silicon containing crystalline substrate at the bottom of the angled trench to produce a surface along (111) crystal plane direction;
• and
• forming a crystalline material comprising a Group III element and a Group V element in the angled trench by epitaxial growth.