Saturday, February 13, 2016

TSMC Belgium & Sweden demonstrate first un-strained InAs FinFETs

Researchers led by TSMC R&D Europe B.V. in Leuven Belgium (Imec) and Lund Sweden (Lund Nano Lab), claim the first demonstration of an unstrained indium arsenide (InAs) fin field-effect transistor (finFET) with 20nm fin height (Hfin) [R. Oxland et al, IEEE Electron Device Letters, published online 29 January 2016]. The team also included researchers from University of Glasgow in the UK, Texas State University in the USA, and TSMC in Taiwan.

The gate insulation consisted of 5nm ZrO2 deposited by ALD, yielding an 1.2 nm equivalent oxide thickness (EOT). 

 
(a) Layer structure used, showing the pseudomorphic InAlAs etch-stop layer and (b) process flow for fabrication of InAs finFETs, starting with first step after wafer growth. (Figure from Semiconductor Today)

Full story here by Mike Cooke in Semiconductor Today and the IEEE Electron Devices abstract below.

InAs FinFETs with Hfin = 20 nm fabricated using a top-down etch process

Oxland, R. Li, X. ; Chang, S. ; Wang, S. ; Vasen, T. ; Ramvall, P. ; Contreras-Guerrero, R. ; Rojas-Ramirez, J. ; Holland, M. ; Doornbos, G. ; Chang, Y. ; Macintyre, D. ; Thoms, S. ; Droopad, R. ; Yeo, Y. ; Diaz, C. ; Thayne, I. ; Passlack, M.

 IEEE Electron Device Letters, published online 29 January 2016

We report the first demonstration of InAs FinFETs with fin width Wfin in the range 25–35 nm, formed by inductively coupled plasma etching. The channel comprises defect-free, lattice-matched InAs with fin height Hfin = 20 nm controlled by the use of an etch stop layer incorporated into the device heterostructure. For a gate length Lg = 1 nm, peak transconductance gm,peak = 1430 µS/µm is measured at Vd = 0.5 V demonstrating that electron transport in InAs fins can match planar devices.