A LASER-RECRYSTALLIZATION TECHNIQUE FOR SILICON-TFT INTEGRATED-CIRCUITS ON QUARTZ SUBSTRATES AND ITS APPLICATION TO SMALL-SIZE MONOLITHIC ACTIVE-MATRIX LCDS

A novel technique for laser-recrystallization of polysilicon films on quartz substrates has been developed for fabricating high-frequency silicon-TFT integrated circuits. The technique features the use of the connected-island structure for forming recrystallized silicon films with enlarged grain size controlled by the thermal gradient. This new technique has been applied to fabricating the driver circuits of small-size monolithic active-matrix LCD’s. A horizontal driver circuit with partially recrystallized silicon TFT’s has been successfully fabricated on quartz substrates together with a vertical driver and active-matrix TFT circuits. It has been shown that the operating frequency of the fabricated horizontal driver circuits can be as high as 10 MHz under a clock voltage of 5 V. © 1990 IEEE