Type III-V and type IV semiconductor device formation

A method of forming a semiconductor device comprising:

• forming a first semiconductor layer directly on a silicon substrate, the first semiconductor layer having a first region adjacent to an interface between the first semiconductor layer and the silicon substrate and a second region adjacent to the first region, the first region including a first concentration of defects and the second region including a second concentration of defects;
• forming a first insulating layer directly on the first semiconductor layer;
• forming a second semiconductor layer directly on the first insulating layer;
• forming an insulating trench in the second semiconductor layer and the first insulating layer defining a first portion of the second semiconductor layer and a first portion of the first insulating layer electrically insulated from a second portion of the second semiconductor layer and a second portion of the first insulating layer;
• removing the second portion of the second semiconductor layer and the second portion of the first insulating layer;
• and
• forming a third semiconductor layer directly on the first semiconductor layer adjacent to the insulating trench such that the third semiconductor layer is electrically insulated from the first portion of the second semiconductor layer and the first portion of the first insulating layer;
• wherein the first semiconductor layer and the third semiconductor layer are each a type III-V semiconductor and the second semiconductor layer is a type IV semiconductor, and wherein the second concentration of defects is less than the first concentration of defects.