Advances in laser annealing technology for poly-Si material engineering and ultra-high-performance device fabrication

High quality poly-Si microstructure is needed for the fabrication of high-quality poly-Si thin-film-transistors (TFTs). TFTs are the building blocks of modem active matrix LCDs (AMLCDs). The level of device performance determines the degree of on-panel integration. High integration is desirable for innovative, high-value-added products. The crystallization process is a very critical step of the TFT fabrication process. Crystallization technologies have evolved significantly over the past 20 years with a variety of methods that aim at improving different features of the process and/or the poly-Si microstructure. This paper presents the motivation behind this evolution process in the crystallization technology. We discuss in detail the different aspects of various crystallization techniques and provide arguments and data supporting our belief that lateral crystallization technology possesses the best collection of features to enable the formation of very high-quality poly-Si films compatible with the fabrication of ultra-high performance poly-Si TFT devices. Such high quality, structurally-engineered poly-Si films are well-suited for the requirements of the next generation AMLCDs and may also find applications in other, nondisplay areas, such as 3 dimensional ICs.