Patent ID: 7510956

Claim:
A method for forming a semiconductor device with a multilayered gate structure resistant to migration of a mobile species and overlying a channel region of the device, comprising: providing a semiconductor substrate having an upper surface; forming on the upper surface a stack of overlying layers in various orders, comprising: a gate oxide layer having an interface in contact with the upper surface; a first conductor layer comprising a metal oxide; a first absorption layer of a conductive absorption material having a higher affinity for oxygen than the first conductor layer for reducing migration of the mobile species toward the interface; a second conductor layer comprising the metal oxide; a second absorption layer comprising the conductive absorption material that is formed on an opposing side of the second conductor layer from the first absorption layer; and a third conductor layer; and removing portions of the stack of layers lying laterally outside a region desired to be the channel region of the device, thereby forming the multi-layered gate structure having multiple alternating layers of the metal oxide and the conductive absorption material between the gate oxide layer and the third conductor layer overlying the channel region of the device.