High performance strained Si0.5Ge0.5 quantum-well p-MOSFETs fabricated using a high-κ/metal-gate last process

• A SiGe QW p-MOSFET was fabricated using high-κ/metal gate last process.
• The lower VT and thinner IL benefit from the HKMG-last process.
• Hole mobility of SiGe QW device 2.74 times the SOI device’s hole mobility.

A high-κ/metal-gate (HKMG) last process for fabricating strained Si0.5Ge0.5 quantum-well (QW) p-channel metal oxide semiconductor field effect transistors (p-MOSFETs) is presented. Because the HKMG was formed after the ion-implant doping activation process, the thermal budget issue could be mitigated. The transistor features good transfer and output characteristics with Ion/Ioff ratio up to 106 and threshold voltage (VT) down to 0.1 V. The effective hole mobility of the SiGe QW transistor reaches 215 cm2/V s for strong inversion conditions, which is 2.74 times the SOI device’s hole mobility.