Low-Temperature (∼ 250°C) Cu-Induced Lateral Crystallization of Amorphous Ge on Insulator

Abstract

Metal-induced lateral crystallization (MILC) of amorphous Ge has been investigated to realize low temperature formation of poly-Ge films on insulating substrates. From a comparative study of MILC with various catalysis metals (Ni, Co, Pd, and Cu), it was found that Cu enhanced both nucleation and subsequent nucleus growth the most significantly among the species. Consequently, low temperature ( 250C) growth with a high velocity (1 m/h) of poly-Ge films becomes possible by employing Cu as the cat-alyst. This technique will accelerate the realization of advanced high-speed TFT on flexible substrates. VC 2011 The Electrochemical Society. [DOI: 10.1149/1.3582794] All rights reserved. Manuscript submitted January 27, 2011; revised manuscript received April 4, 2011. Published April 19, 2011. In order to break through the scaling limit of complementary metal-oxide-semiconductor transistors, new channel materials such as strained Si and Ge are being employed.1–6 Such an approach is also attractive to improve the performance of thin-film transistors (TFT). Low-temperature processing of these channel materials is important for the TFT application. To realize flexible TFTs for advanced multi-functional displays, the crystallization temperature should be lower than the softening temperature ( 300C) of flexi-