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The electrical and optical properties of amorphous indium gallium zinc oxide (a-IGZO) thin films and thin film transistors (TFTs) were investigated for their applications in flat panel displays (FPD). The device characteristics were found to be sensitive to gate dielectric and interlayer film material. TFTs using SiO 2 as a gate dielectric and passivation showed very good characteristics when measured in the dark, with mobility above 10 cm 2 V À1 s À1 , on/off ratio of %10 8 , sub-threshold swing less than 0.2 V/decade and the threshold voltage (V th ) 0.9 V. However when exposed to light of wavelength below 420 nm V th shifted markedly. The shift in V th increased with increasing power density, irradiation time, and decreasing wavelength. The shift is attributed to trapping of photogenerated holes in the light induced traps in SiO 2 close to the IGZO interface. It is postulated that these traps are created due to the unstable IGZO surface. Shielding TFTs from light stabilizes the characteristics, however, stabilization of the IGZO surface is required to realize stability for practical applications.

A method for measuring acid generation efficiency is presented and utilized to determine the relative efficiency of four photoacid generators (PAGs) upon radiation with photon, electron, and ion beams. In this method, chemically amplified resists are prepared with varying amounts of base, coated into thin films (1000 AA), and exposed. Linear plots of the base concentration against the threshold exposure dose for each resist yield the threshold acid concentration and the acid generation rate constant for each PAG. The acid-generating efficiency of the four PAGs (ND-Tf, TPS-Tf, TBI-PFOS, and TBI-Tf) upon irradiation with DUV (248 nm), EUV (13.4 nm), X-ray (1 nm), e beam (30 and 50 keV), and He+ ions is evaluated