Abstract: This is an integrated device which comprises an integrated transistor and resonant tunneling diode where the transistor comprises a substance 10, a buffer layer layer 12 over the substrate 10, and a channel layer 14 over the buffer 12; and the resonant tunneling diode (RTD) comprises a first contact layer 18, a first tunnel barrier layer 20 over the first contact layer 18, a quantum well 22 over the first tunnel barrier layer 20, a second tunnel barrier layer 24 over the quantum well 22, and a second contact layer 26 over the second tunnel barrier layer 24. Other devices and methods are also disclosed.

Abstract: A lateral resonant tunneling transistor is provided comprising heterojunction barriers (24) and a quantized region (33). Current between source contact (26) and drain contact (28) can be switched "ON" or "OFF" by placing an appropriate voltage on gate contacts (30) and (32). The potential on gate contacts (30) and (32) selectively modulate the quantum states within quantized region (33) so as to allow electrons to tunnel through heterojunction barrier (24) and quantized region (33).

Abstract: A lateral resonant tunneling transistor is provided comprising heterojunction barriers (24) and a quantized region (33). Current between source contact (26) and drain contact (28) can be switched "ON" or "OFF" by placing an appropriate voltage on gate contacts (30) and (32). The potential on gate contacts (30) and (32) selectively modulate the quantum states within quantized region (33) so as to allow electrons to tunnel through heterojunction barrier (24) and quantized region (33). The method for fabricating comprises etching trenches through second barrier layer (20) and quantum layer (76) and regrowing a semiconductor to form heterojunction barrier (24).

Abstract: An epitaxial stack (10) is provided that allows integration of both vertical and horizontal quantum effect devices. Epitaxial stack (10) allows fabrication of both quantum well resonant tunneling transistors (27) and Stark-effect transistors (34), thus allowing for circuit integration of different quantum effect devices in the same epitaxial stack.

Abstract: A controlled in situ etch-back technique is disclosed in which an etch melt 17 and a growth melt 18 are first saturated by a source-seed crystal 15 and thereafter etch-back of a substrate 14 takes place by the slightly undersaturated etch melt, followed by LPE growth of a layer by the growth melt, which is slightly supersaturated.