Method to eliminate re-crystallization border defects generated during solid phase epitaxy of a DSB substrate

A method for fabricating an integrated circuit, comprising:

• providing a hybrid orientation substrate having a first silicon layer with one of a (100) or (110) crystalline orientation directly bonded to a second silicon layer with the other of the (100) or (110) crystalline orientation;
• amorphizing a selected area of the first silicon layer by ion implantation, leaving a remaining area of the first silicon layer unamorphized;
• recrystallizing the amorphized selected area into the other of the (100) or (110) crystalline orientation using the second silicon layer as a crystal template for the recrystallization;
• growing a silicon oxide layer over the first silicon layer, including over a border region at a surface of the first silicon layer between the recrystallized selected area and the unamorphized remaining area, by thermally oxidizing the first silicon layer at a temperature of less than about 900° C., whereby the thermal oxidation can encompass at least a portion of at least one of any border region defect associated with the crystal orientation differences of the recrystallized selected area and the unamorphized remaining area;
• removing the silicon oxide layer, whereby any encompassed portion of the at least one of any border region defect will be simultaneously removed, thereby reducing a lateral width of the at least one of any border region defect;
• and
• following removal of the silicon oxide layer, forming a shallow trench isolation region in the border region, whereby formation of the shallow trench isolation region can remove a remaining portion of the at least one of any border region defect with reduced lateral width.

A method for fabricating an integrated circuit, comprising:

• providing a hybrid orientation substrate having a semiconductor top layer with a first crystalline orientation directly bonded to a semiconductor handle layer with a second crystalline orientation different from the first crystalline orientation;
• amorphizing a selected area of the top layer, leaving a remaining area of the top layer unamorphized;
• recrystallizing the amorphized selected area into the second crystalline orientation using the handle layer as a crystal template for the recrystallization, the recrystallization generating a border defect in a border region at a surface of the top layer between the recrystallized amorphized selected region and the unamorphized remaining region, the border defect having a first lateral width and a depth;
• growing a sacrificial oxide layer over the top layer by thermally oxidizing the top layer, including over the border region, whereby the sacrificial oxide layer encompasses a portion including the first lateral width and at least part of the depth of the border defect;
• removing the sacrificial oxide layer, whereby the encompassed portion of the border defect is simultaneously removed, thereby reducing the border defect to a lateral width less than the first lateral width;
• and
• following removal of the sacrificial oxide layer, forming a shallow trench isolation region in the top layer including in the border region, the shallow trench isolation having a lateral width less than the first lateral width and the shallow trench isolation region encompassing at least a portion of any remaining part of the border defect.