In this letter, we report on the impact of a PEALD-AlN interfacial passivation layer (IPL) and an in-situ NH3 post remote-plasma (PRP) treatment onto InGaAs quantum-well MOSFETs with Ti/HfO2/InGaAs gate stack. Transistors with gate lengths down to 80 nm have been fabricated and characterized. Due to the excellent interfacial quality of HfO2/AlN/InGaAs, the subthreshold swing and the peak effective channel mobility have been improved to 93 mV/decade and 4253 cm2/Vs, respectively. The drain current has also shown a 4.6-fold enhancement, to 164mA/mm(IOFF = 100 nA/μmandV DD =0.5V),compared with the HfO2 control device. The results also show that the HfO2/AlN device exhibits better immunity to short-channel effects (SCEs) than the HfO2 control device. Furthermore, during positive bias temperature instability stress, a smaller VTH and a lower Gm were observed for the sample with an AlN IPL and NH3 PRP treatment, indicating that it is more reliable than the sample without any IPL or plasma treatment.
- high-κ dielectric
- interfacial passivation layer (IPL)
- NH plasma treatment
- plasma-enhanced atomic layer deposition (PEALD)
- Quantum-well MOSFET (QW-MOSFET)