Effect of chemical mechanical polish process on low-temperature poly-SiGe thin-film transistors

Abstract

The improvement of polycrystalline silicon germanium thin-film transistors (poly-SiGe TFTs) using NH(3) passivation and chemical mechanical polishing (CMP) process was examined. Experimental results indicated that NH(3) passivation could effectively improve the turn on characteristics. Moreover, the TFTs fabricated on polished poly-SiGe film exhibit: higher carrier mobility, better subthreshold swing, lower threshold voltage, and higher on/off current ratio due to the smooth poly-SiGe interface.