FORMATION OF SOURCES DRAINS USING SELF-ACTIVATION TECHNIQUE ON POLYSILICON THIN-FILM TRANSISTORS/

Source/drain formation by ion doping using self-activation technique w ithout thermal anneal on polysilicon thin film transistors (TFT's) hav e been investigated. Phosphorus ions and protons were simultaneously i mplanted into polysilicon films. At total ion doses over 8 x 10(15) io ns/cm(2), resistivities of self-activated films have been found equal to those of the ones annealed after the implantation. This self-activa tion technique enabled us to fabricate self-aligned TFT's having low-r esistance Al gates and, at the same time, to hydrogenate active layers . With the case of Self-activation technique, field-effect mobilities as high as 58 and 49 cm(2)/(V.s) were achieved in n-channel and p-chan nel TFT's, respectively, fabricated on glass substrates.