Enhancement mode n -channel Si/SiGe MODFET with high intrinsic transconductance

Publisher Website
Google Scholar
Abstract
n-channel Si/SiGe MODFETs with quantum wells grown on a thick (1.5μm) graded buffer (Ge 5–30%) are realised. MODFETs with a surface gate work in the depletion mode due to a large gate-to-2-DEG channel distance of 75 nm. MODFETs with a recessed gate 10–15 nm above the channel exhibit enhancement mode operation with significantly high extrinsic transconductances of 340 mS/mm or 670 mS/mm at 300 K or 77 K and corresponding intrinsic transconductances of 38O mS/mm or 800 m S7/mm. The performance indicates the improved layer quality on graded buffers.