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FinFET is a promising device candidate for 14nm node CMOS technology. We have developed FinFET device showing superior short channel control at 25nm gate length. This FinFET device featuring gate first high-k/metal gate and merged Epi source/drain process. Key process improvements to resolve the FinFET unique challenges are presented. High drive currents have been obtained for both nFET and pFET. All these results show FinFET is the most promising candidate for 14nm node CMOS technology.

A first time rigorous experimental study of effective current (Ieff) variability in high-volume manufacturable (HVM) 14nm Silicon-On-Insulator (SOI) FINFETs is reported which identifies, threshold voltage (Vtlin), external resistance (Rext), and channel trans-conductance (Gm) as three independent sources of variation. The variability in Gm, Vtlin (AVT=1.4(n)/0.7(p) mV-μm), and Ieff exhibit a linear Pelgrom fit indicating local variations, along with non-zero intercept which suggests the presence of global variations at the wafer level. Relative contribution of Gm to Ieff variability is dominant in FINFETs with small number of fins (Nfin); however, both Gm and Rext variations dominate in large Nfin devices. Relative contribution of Vtlin remains almost independent of Nfin. Both n and p FINFETs show the above mentioned trends.

This work presents SOI finFETs with fin width (Dfin) scaled to sub 15nm. The process flow provides robust Dfin scaling as depicted by the universal electrostatic scaling of the DIBL and sub-threshold swing (SS). The high field long channel mobility drops by ~6% with Dfin scaling, however, DIBL and SS improves by ~1.5X and ~2X, respectively, for 20nm channel length n/pfinFETs. The effective current (Ieff) at fixed Ioff improves by ~20% and ~30% for p and n finFETs, respectively, with Dfin scaling.

In this work, we present a study of the growth and electrical characteristics of metalorganic atomic layer deposited (MO-ALD) HfO2 films deposited using a 300 mm Counter-Flow ALD platform. HfO2 films were deposited over a large range of process temperatures, and flow rates in order to fully characterize the MOALD process window. The HfO2 films were characterized using AFM, HRTEM, MEIS, and SIMS. Saturation curves were generated for precursor and ozone oxidant over a 150 ºC process temperature window, using two different flow rates of Hf precursor. The use of water versus ozone as an oxidant was also investigated. Since all depositions take place above the decomposition temperature of the precursor, it is critical to understand and control the rate of thermal decomposition or parasitic CVD in the process in order to realize good uniformity in a traveling wave-type system. Thus, we have measured the rate of thermal CVD over the full range of temperatures. The thermal CVD rate shows a concave Arrhenius behavior as the process rises in temperature and transitions from an ALD dominated growth mechanism to a CVD dominated mechanism. We propose a possible explanation for this behavior. In addition to the growth characteristics, we have investigated the electrical properties of the as-deposited films using in-line Quantox measurements, and gate stack structures using integrated devices. The relationship between process and electrical characteristics will be discussed.