Binary superlattice tunneling device and method

• US 4,851,886 A
• Filed: 06/11/1986
• Issued: 07/25/1989
• Est. Priority Date: 06/11/1986
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Reed, Mark A., Lee, Jhang W.
• Primary Examiner(s): James, Andrew J.
• Assistant Examiner(s): Ngo, Ngan V.
• Application Number:
  US06/872,795
• Time in Patent Office: 1,140 Days
• Field of Search: 357/16, 357/4, 357/4 SL, 357/12, 357/14
• US Class Current: 257/17
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H01L 29/155 Comprising only semiconductor materials H01L29/154 takes precedence
• CPC Class Codes: H01L 29/882 Resonant tunneling diodes, i.e. RTD, RTBD

Abstract

A resonant tunneling diode (30) with anode (40) and cathode (32) separated by binary short-period superlattice tunneling barriers (34,38) with a quantum well (36) between is disclosed. Enhancement and depletion mode diodes are disclosed.

Claims

1. A resonant tunneling device, comprising:

(a) a planar quantum well made of a first semiconductor material;

(b) first and second planar tunneling barriers planarly abutting said well, said tunneling barriers each a short-period superlattice of alternating layers of second semiconductor material and third semiconductor material with said second and third materials each a binary compound;

(c) a first terminal planarly abutting said first tunneling barrier, said first terminal made of doped fourth semiconductor material; and

(d) a second terminal planarly abutting said second tunneling barrier, said second terminal made of doped fifth semiconductor material;

(e) wherein the bandgap of said first material is less than the effective bandgap of both of said tunneling barriers, and the bandgap of said fourth material is less than the effective bandgap of said first tunneling barrier, and the bandgap of said fifth material is less than the effective bandgap of said second tunneling barrier;

(f) whereby resonant tunneling of carriers from said first terminal through a subband in said well into said second terminal is controlled by the bias applied across said terminals.

2. The device of claim 1, wherein:

(a) said first, third, fourth, and fifth materials are GaAs; and

(b) said second semiconductor material is AlAs.

3. The device of claim 1, wherein:

(a) said first material is InGaAs;

(b) said second material is AlAs; and

(c) said third, fourth, and fifth materials are GaAs.

4. The device of claim 1, wherein:

(a) said short-period superlattices each have five layers, with three layers of said second material and two layers of said third material.

5. The device of claim 1, wherein:

(a) each of said layers in said short-period superlattices is two molecular layers thick.