AVS 47th International Symposium
    Magnetic Interfaces and Nanostructures Wednesday Sessions
       Session MI+EL-WeA

Paper MI+EL-WeA6
Non-Volatile Reprogrammable Logic Elements using a Hybrid RTD-GMR Circuit@footnote 1@

Wednesday, October 4, 2000, 3:40 pm, Room 206

Session: Magnetic Semiconductors and Hybrid Structures II
Presenter: A.T. Hanbicki, Naval Research Laboratory
Authors: A.T. Hanbicki, Naval Research Laboratory
R. Magno, Naval Research Laboratory
S.-F. Cheng, Naval Research Laboratory
J.E. Mattson, Naval Research Laboratory
Y.D. Park, Naval Research Laboratory
A.S. Bracker, Naval Research Laboratory
B.R. Bennett, Naval Research Laboratory
B.T. Jonker, Naval Research Laboratory
Correspondent: Click to Email
Programmable logic devices and gate arrays are increasingly important in new computation and digital logic systems. The resonant tunneling diode (RTD) is an especially attractive device component for such applications because it offers high frequency and low power operation due to its unique IV characteristics. It has been shown that memory, multi-value logic and monostable-bistable logic elements (MOBILE)@footnote 2@ can be constructed using RTDs and FETs. We describe here the fabrication and operation of programmable gates and logic cells based on the combination of RTDs with magnetic elements, yielding fully reprogrammable, nonvolatile functions. The circuits discussed are constructed with resonant interband tunneling diodes (RITD) combined with giant magneto-resistance (GMR) elements. The RITDs are fabricated from MBE-grown InAs/AlSb/GaSb/AlSb resonant tunneling structures using standard processing techniques, and provide a peak current of 1.4 x 10@super 4@ A/cm@super 2@. The GMR elements consist of Co/Cu multilayers, and exhibit a value of @DELTA@R/R = 28% at 300 K (CIP). Simple series and parallel circuit combinations demonstrate continuous or 2-state tunability of the RITD I-V characteristic. Threshold detection is demonstrated, for the RITD and GMR in series, by ramping the magnetic field. With the elements we have chosen, the output can be switched by 0.5 V. MOBILE-like inverter operation is observed in a GMR/2-RITD circuit. Specifics of several other circuits will also be discussed. Work is in progress to fabricate an on-chip GMR/RITD integrated circuit. @FootnoteText@ @footnote 1@This work was supported by the Office of Naval Research. @footnote 2@K. Maezawa and T. Mizutani, Jpn. J. Appl. Phys., 32 (1993) L42.