Single Wafer sSOI by SIMOX

Globally strained (tensile) silicon-on-insulator (sSOI) is being studied extensively to obtain higher performance CMOS. sSOI offers three key advantages over bulk-Si: (i) reduced parasitic capacitance; and (ii) enhanced electron mobility; and (iii) compatibility with ultra thin SOI device design. Conventionally, sSOI is fabricated by wafer bonding and layer transfer of strain Si. Although this technique has successfully been used to produce sSOI substrates, its fabrication cost is a concern for commercial applications. Some of the key process/substrate elements in fabricating such sSOI include: (i) a device wafer that contains epitaxially grown thick graded buffer layers (GBL) of SiGe with strain-Si on top; (ii) deposition of an oxide layer on (i); (iii) bonding of the device wafer with a handle wafer (bulk-Si); and (iv) layer transfer of strain-Si/oxide stack onto the handle wafer. This work was aimed at finding lower cost alternatives to fabricate sSOI substrates. We demonstrate that sSOI can be fabricated by separation of implanted oxygen (SIMOX) method using only a single wafer (described as the device wafer above). The method is compatible with existing commercial SIMOX process