Improvement of thin silicon on sapphire (SOS) film materials and device performances by solid phase epitaxy

The increased emphasis on sub-micron CMOS/SOS devices has placed a demand f or high quality thin silicon on sapphire (SOS) films with thickness of the order 100-200 nm. It is demonstrated that the crystalline quality of as-gro wn thin SOS films by the CVD method can be greatly improved by solid phase epitaxy (SPE) process: implantation of self-silicon ions and subsequent the rmal annealing. Subsequent regrowth of this amorphous layer leads to a grea ter improvement in silicon layer crystallinity and channel carrier mobility , evidenced, respectively, by double crystal X-ray diffraction and electric al measurements. We concluded that the thin SPE SOS films are suitable for application to high-performance CMOS circuitry. (C) 2000 Elsevier Science S .A. All rights reserved.