Method to form thick relaxed SiGe Layer with trench structure

A method of forming a SiGe layer having a relatively high germanium content and a relatively low threading dislocation density, comprising:

• preparing a silicon substrate;
• depositing a layer of SiGe to a thickness of between about 100 nm to 500 nm, wherein the germanium content of the SiGe layer is greater than 20%, by atomic ratio;
• implanting H+ ions into the SiGe layer at a dose of between about 1·1016 cm−2 to 5.1016 cm−2, at an energy of between about 20 keV to 45 keV;
• patterning the SiGe layer with photoresist in a checkerboard pattern;
• plasma etching the structure to form trenches about regions having side dimensions less than or equal to 4μ×4μ;
• removing the photoresist;
• and
• thermal annealing the substrate and SiGe layer, to relax the SiGe layer, in an inert atmosphere at a temperature of between about 650° C. to 950° C. for between about 30 seconds and 30 minutes.

A method of forming a SiGe layer having a relatively high germanium content and a relatively low threading dislocation density, comprising:

• preparing a silicon substrate;
• depositing a layer of SiGe to a thickness of between about 100 nm to 500 nm, in a graded structure, wherein the germanium content of the SiGe layer is about 20%, by atomic ratio, adjacent the silicon substrate and about 30% at the top of the SiGe layer, at a temperature of between about 400° C. to 600° C.;
• implanting H+ ions into the SiGe layer at a dose of between about 1·1016 cm−2 to 5·1016 cm−2, at an energy of between about 20 keV to 45 keV;
• patterning the SiGe layer with photoresist in a checkerboard pattern;
• plasma etching the structure to form trenches about regions;
• removing the photoresist;
• and
• thermal annealing the substrate and SiGe layer, to relax the SiGe layer, in an inert atmosphere at a temperature of between about 650° C. to 950° C. for between about 30 seconds and 30 minutes.