Amorphous silicon metal insulator semiconductor (MIS) capacitor, which includes an amorphous silicon thin film embedded in the silicon nitride gate dielectric stack, has been prepared and characterized for memory functions. The capacitor's current-voltage and capacitance-voltage hysteresis curves showed strong charge trapping and detrapping phenomena. The embedded amorphous silicon film enhanced charge retention in the dielectric film. The 9 nm embedded a-Si:H layer had a charge storage capacity six times that of the capacitor without the embedded layer. This kind of nonvolatile memory device can be used in many low-temperature circuits.