Browse Prior Art Database

Isochemical - Isostructural Tunneling Junctions

IP.com Disclosure Number: IPCOM000102283D
Original Publication Date: 1990-Nov-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 2 page(s) / 60K

Publishing Venue

IBM

Related People

Cuomo, JJ: AUTHOR [+3]

Abstract

Superconducting tunneling junctions particularly refractory Nb2O5 multioxidation state transition metals are difficult to produce with a sharp boundary between the tunneling couple. The interface between a superconductor and a tunneling barrier can be made of the same material such that chemical and structural compatibility are achieved.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 63% of the total text.

Isochemical - Isostructural Tunneling Junctions

       Superconducting tunneling junctions particularly
refractory Nb2O5 multioxidation state transition metals are difficult
to produce with a sharp boundary between the tunneling couple.  The
interface between a superconductor and a tunneling barrier can be
made of the same material such that chemical and structural
compatibility are achieved.

      Device structures and processes for their fabrication are
described herein that are both isostructural and isochemical.  This
is a unique combination that has never been described before.  An
added feature to this unique system is that the superconductors have
a high Tc.  The first system is ZrN (see figure) which is prepared by
the reactive sputtering of ZrN in a partial pressure of N2 . The N/Zr
= 1; A0 = 4.57; NaCl structure; R. T. p  = 15mLcm; Tc = 9.1oK.

      An insulating layer N/Zr = 1.42, which is an insulating phase,
is produced by sputtering in 100% N2 .  The material also has the
NaCl structure with A0 = 4.63 Ao and a bandgap of 2 eV.  A counter
electrode of another superconductor is deposited, producing the
superconducting configuration.

      The same configuration applies to HfN N/Hf = 1; A0 = 4.52; NaCl
structure; p = 57mLcm; Tc = 7.9oK.  The structure is illustrated in
the figure.

      A general process for preparing these tunneling configurations
comprises depositing the superconducting electrode by reactive
deposition (sputteri...