Method for fabrication of polycrystalline silicon thin film transistors

Abstract

The present invention provides a method for fabrication of polycrystalline silicon thin film transistors, which forms a silicon spacer on the sidewall of the active layer of a thin film transistor (TFT) by way of anisotropic plasma etching in a single direction. The silicon spacer provides a mechanism for laser recrystallization on the sidewall to prevent the active layer from shrinkage or shelling-off after the laser recrystallization. According to the present invention, large grains can be formed in the channel without additional mask during production. By doing so, the characteristics of the components are enhanced; the uniformity is improved; and, the production cost is lowered. Therefore, this technique will play an important role in the fields of low temperature polycrystalline silicon thin film transistor (LTPS-TFT).