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We report the effects of UV-ozone oxidation, oxide removal etch chemistry (dilute HCl or concentrated NH4OH), semiconductor doping, and annealing on the contact resistivity (rhoc) of Ti0.1W0.9 refractory alloy to n-type InGaAs. The semiconductor surface was oxidized through exposure to UV-ozone, then subsequently etched by either dilute HCl or concentrated NH4OH before TiW contacts were deposited by blanket sputtering. InGaAs samples doped at 5 times 1019 cm-3, treated with 10 minutes of UV-Ozone then one minute dilute HCl exhibited rhoc of (1.90 plusmn 0.35) times 10-8 Omega-cm2. The contacts are thermally stable at least to 400 degC where after one minute anneal, rhoc reduced to (1.29 plusmn 0.28) times 10-8 Omega-cm2. TiW contacts on samples having same active dopants, with no UV-ozone oxidation and only 10 seconds of concentrated NH4OH etch exhibit rhoc of (2.49 plusmn 0.40) plusmn 10-8 Omega-cm2.