Masaya Kunigita

A full-color LCD addressed by poly-Si TFTs fabricated below 450 degrees C

Poly-Si thin-film transistors (TFTs) fabricated with a maximum processing temperature of 450 degrees C by means of laser-induced crystallization of a-Si are discussed. These devices show high mobilities (50 cm/sup 2//V-s), low threshold voltages (2 V), low off current (10/sup -12/ A), and high reliability. A 3.5-in.-diagonal full-color liquid-crystal display addressed by these poly-Si TFTs is presented. >

Low Temperature Polysilicon TFTs by Non-Mass-Separated Ion Flux Doping Technique

A low temperature and hi8h throughput self aligned poly-Si TFT fabrication process has been developed. The process includes two key techniques. The first one is a laser induced crystallization of a-Si, occurring in the solid phase, using a high beam scanning speed. The second is a large diameter ion flux doping without nass separation. The maximum processing temperature is 450t, which is sufficiently low to use inexpensive glass substrates. With this process, exeellent poly-Si TFT characieristics of Ion/Ioff>106 and 4 ru=40em2/ys were obtained.

Low temperature fabrication of poly-Si TFT by laser induced crystallization of a-Si

Abstract Poly-Si TFTs were fabricated by means of laser-induced crystallization of PECVD a-Si in which the maximum process temperature was 450°C. These devices showed high field effect mobilities (50cm2/Vs), low off current (10–12A), and high reliability. A 3.5-in diagonal full-color LCD addressed by these poly-Si TFTs was fabricated and produced beautiful video images.

A full colour LCD addressed by poly Si TFTS fabricated at low temperature below 450 degrees C

A process below 450 degrees C has been developed for poly-Si thin-film transistor (TFTs). The devices have higher mobility ( approximately 50 cm/sup 2//V-s) and higher reliability than a-Si TFTs. A 3.5-in. full-colour liquid-crystal display addressed by these poly-Si TFTs is described.<<ETX>>

Low-Temperature Polysilicon Thin Film Transistors by Non-Mass-Separated Ion Flux Doping Technique

A low-temperature, high-throughput self-aligned poly-Si TFT fabrication process has been developed. The process includes two key techniques. The first one is a laser-induced crystallization of a-Si occurring in the solid phase using a CW Ar+ laser beam with high scanning speed, which was previously reported. The second is large-diameter ion flux doping without mass separation. The maximum processing temperature is 450°C, which is sufficiently low for use of inexpensive glass substrates. With this process, excellent poly-Si TFT characteristics of Ion/Ioff>106 and µFE=40 cm2/(V s) were obtained.

Low-leakage current polysilicon TFTs for LCD pixel addressing

The leakage current characteristics of low-temperature polysilicon TFTs (thin-film transistors) below 450 degrees C have been investigated. It was confirmed that the laser-induced crystallized polysilicon with temperature below 450 degrees C has good physical properties and device characteristics in TFT, equal to those of polysilicon with a process temperature of around 600 degrees C. Reduction of leakage current at higher signal voltage could be achieved by the optimization of the geometrical structure with the laser-induced crystallized polysilicon TFT. The low leakage current characteristics at the higher signal voltage may enlarge the applicable field in the higher-performance display. For example, these improved characteristics make it possible to apply higher voltage for addressing pixels of normally white TN and LC (liquid crystal) polymer composite mode.<<ETX>>

Display-Special Contribution from IDW '98. Reflective-type polymer dispersed LC-mode Projection Display.

A new compact projection display has been developed using light valves based on a 2-inch diagonal low-temperature poly-Si TFT reflective XGA array and polymer dispersed LC-mode, 120-W ultrahigh-pressure short-arc lamp (UHP lamp), and simple optical components. Luminous flux of 1400 ANSI-lm, contrast ratio of 85, and the illuminance homogeneity of 90% were achieved. Simulation by basic optical theory in concentrators and experiments with a simplified reflective-type polymer dispersed LC-mode light valve indicates that the performance could be improved in future up to a luminous flux of 1600 ANSI-lm with contrast ratio of more than 150.

LP-A: Late-News Poster: A Low-Temperature Poly-Si TFT Reflective XGA Array for LCPC Light Valve

A 2 inches in diagonal low temperature poly-Si TFT reflective XGA array with driver integration was fabricated by Ar+ laser annealing method. An opaque organic film was used for a planarization layer of reflective electrodes as well as a light shield layer to the array. We applied the array to LCPC (Liquid Crystal / Polymer Composite) light valve and obtained a high resolution image.