Alvin J Drehman, 6839 Sleigh Rd, Kates Corner, MA 01824

7318948, Jan 15, 2008

Aug 9, 2004

10/914019

Alvin J. Drehman - Chelmsford MA, US

United States of America as represented by the Secretary of the Air Force - Washington DC

B05D 5/06

427162, 427164, 427167, 428423

A thin film of zinc oxide is deposited by sputter deposition in a partial pressure of oxygen on a suitable at a low temperature, such as less than 300 degrees Centigrade, to provide an amorphous film. This should take place in a sputtering environment which will produce an oxygen deficient film layer. After this, the film is crystallized by heat treatment in an oxygen free environment in a given temperature range. The thin film produced by this process will have very low electrical resistance, is transparent from about the visible to beyond 10 microns in wavelength, is highly resistant to laser energy and is highly conductive.

5376626, Dec 27, 1994

Oct 2, 1992

7/956447

Alvin J. Drehman - Chelmsford MA
Stephen Bachowski - Woburn MA

The United States of America as represented by the Secretary of the Air
Force - Washington DC

H01L 3900
H01L 3916
H03K 1792
H03K 338

505234

A superconducting switch is composed of anisotropic magnetic material. The switch has a first superconducting section, a variable resistive section and a second superconducting section. An external magnetic field is applied so that the first and second superconducting sections remain superconducting and the resistive section changes resistance when the magnetic field applied exceeds the critical field of the variable resistance section. The different critical field regions are achieved by exploiting the natural critical field anisotropy of the ceramic superconductors (a previously unobserved phenomena in metal superconductors). By making the different sections with different orientations they will exhibit different critical field valves for a given direction of applied fields. The state of the switch is changed by either increasing or decreasing the external magnetic field about the critical field value of the resistive section of the switch. The first superconducting section is connected to the resistive section and the resistive section is connected to the second superconducting section to form a switch circuit.

5936401, Aug 10, 1999

Sep 19, 1996

8/725200

Alvin Drehman - Chelmsford MA

The United States of America as represented by the Secretary of the Air
Force - Washington DC

G01R 3312
G01R 3316
G01N 2772
H01L 3900

324234

A device and process for determining the uniformity of a superconducting film's critical current density and transition temperature over a large area uses an array of ac coils placed in close proximity to a superconducting film. A variable ac current is passed through each coil which induces a proportional current in the superconducting film. A lock-in amplifier set to the third harmonic of the ac current is put in parallel with the ac current source. When the current in the film exceeds the critical density of the film then the third harmonic is picked up by the lock-in amplifier. In this way one can measure the critical current density of the film at each of the coils. The above coils are mounted within a flat plate (the film side of the substrate is placed against the plate). The entire assembly is cooled within a cryostat so that the temperature can be precisely controlled. This is necessary so that the critical current can be measured as a function of temperature as it varies greatly near the transition temperature and this is the range of interest.

5742073, Apr 21, 1998

Sep 27, 1996

8/725222

Hua Jiang - Mansfield MA
Alvin J. Drehman - Chelmsford MA

The United States of America as represented by the Secretary of the Air
Force - Washington DC

H01L 2906
H01L 3922

257 34

The present invention provides a superconducting switch which has a substrate base and a control line patterned thereon. A buffer layer is deposited on top of these and then a superconducting material is deposited and then patterned wherein the superconducting material forms a strip having multiple intersections with the control line. At each intersection between the control line and the superconducting strip is formed a superconducting gate due to the double step edge junction. The control line underneath provides (1) a means for constructing step edge weak link junctions; (2) a means for heating the weak link junctions; and (3) generating an electromagnetic field near the weak link junctions. In combination, a very small magnetic field can be used to decrease the critical current to a very low level.

4963852, Oct 16, 1990

Mar 15, 1989

7/323636

Alvin J. Drehman - Chelmsford MA

The United States of America as represented by the Secretary of the Air
Force - Washington DC

H01L 2900
H01L 3900

338 32S

A current controlled superconducting switch has a current controlling constriction such that the level of the input determines the condition of the switch. A plurality of the superconducting switches are connected to produce a logic scheme.

5378341, Jan 3, 1995

Oct 13, 1993

8/135827

Alvin J. Drehman - Chelmsford MA
William M. Hale - N. Scituate MA

The United States of America as represented by the Secretary of the Air
Force - Washington DC

C23C 1435
H01L 3924

20429818

The sputtering source of the present invention comprises a means for providing DC or RF power and cooling to a conical target electrode with magnets thereabout and anode at the bottom. At the center of the sputtering source is a grounded anode. A plurality of magnets which form rings are located behind the conical target electrode so that the magnetic field lines point to the anode. The conical target electrode has an inner surface which is slightly inclined from a centerline. The conical target electrode is concentrically located about the vertical centerline. A ground shield is placed about and above the magnets and the conical electrode and further acts to eliminate high energy ions from reaching the substrate because of the shape thereof. An opening in the shield allows for the exit of low energy particles of the target material sputtered from the conical target electrode. The sputtering source provides a narrow beam of target material for deposition on a substrate located at a distance from the source.