FABRICATION OF SELF-ALIGNED ALUMINUM GATE POLYSILICON THIN-FILM TRANSISTORS USING LOW-TEMPERATURE CRYSTALLIZATION PROCESS

The performance of scanning driver circuits fabricated with self-aligned aluminum gate polysilicon thin-film transistors (TFT's) is demonstrated. After the gate electrode patterning, the fabrication process temperature is kept below 400 degrees C to enable the use of aluminum gate electrodes. The low-temperature crystallization phenomenon, which occurs when protons are implanted simultaneously with boron or phosphorus dopants, is employed to eliminate the 600 degrees C activation-annealing process. A maximum clock frequency of about 2.0 MHz is achieved when the driver operating voltage is 24 V and the TFT channel length is 12 mu m.