Sensor with doped microcrystalline silicon channel leads with bubble

Abstract

A sensor device includes a sensing element and a thin film transistor (TFT), and the TFT's channel leads include semiconductor channel leads formed in a layer of microcrystalline silicon (.mu.c-Si). The sensing element is formed in a semiconductor layer that includes silicon-based material and is over the .mu.c-Si layer. Each of the semiconductor channel leads has a structure that prevents formation of bubbles at the lower and upper sides of the .mu.c-Si layer during production of the sensing element. The TFT's channel can be formed in a layer of intrinsic silicon-based material under the .mu.c-Si layer and the .mu.c-Si layer can be a deposited doped layer; or the TFT's channel can be formed in an intrinsic .mu.c-Si layer in which the leads are formed by implanting a dopant. The .mu.c-Si layer can include a sufficiently small amount of hydrogen to prevent formation of bubbles; it can include crystalline grain structures permitting hydrogen to dissipate at a sufficient rate to prevent formation of bubbles; or it can have interfaces sufficiently stable to prevent formation of bubbles.