Showing papers by "Bumman Kim published in 1991"

Method of forming heterostructure field effect transistor

Abstract: A heterostructure field effect transistor having a buffer layer comprising a first compound semiconductor material A layer of second semiconductor material different from the first material is formed over the buffer layer The second layer has a total thickness less than 250 Å A doped third semiconductor layer formed over the second layer The net has a dopant concentration in the second layer is greater than the net dopant concentration in the third layer A gate layer is positioned over the third layer In a preferred embodiment the second layer is a pulse-doped pseudomorphic material There is also provided a method for making the heterostructure field effect transistor A doped pseudomorphic semiconductor layer of a first conductivity type is formed between first and second other semiconductor layers, the second layer including a net dopant concentration of the first conductivity type A Schottky gate electrode is formed in contact with the second layer