Peter B Bischoff, Age 502 Park Ave, Port Jefferson, NY 11777

5973391, Oct 26, 1999

Dec 11, 1997

8/989326

Peter G. Bischoff - Los Altos Hills CA
Ross W Stovall - Fremont CA

Read-Rite Corporation - Milpitas CA

H01L 2302

257678

An interposer for assembly between an integrated circuit and a circuit panel includes an upper insulation layer and a plurality of upper contact pads arranged in a desired pattern in the upper insulation layer. A plurality of micro-devices are formed between the upper insulation layer and a bottom insulation layer having a plurality of lower contact pads arranged in a desired pattern. The upper and the lower contact pads are selectively and electrically interconnected via the micro-devices. The upper and the lower contact pads are overlaid with solder balls to provide the required electrical connection and mechanical coupling between the interposer, the integrated circuit, and the circuit panel. The interposer is made by forming an array of upper contact pads on a substrate; depositing an upper layer of encapsulant material on the substrate; planarizing the substrate and exposing the array of upper contact pads; forming a micro-device; forming an array of lower contact pads; forming a bottom insulation layer; and exposing at least some of the lower contact pads. According to another embodiment, the interposer includes a plurality of electrically conductive terminals that extend outwardly from the lower contact pads for establishing an electrical connection and a mechanical spring action between the integrated circuit and the interposer, in order to absorb excess contraction or expansion.

5949627, Sep 7, 1999

Feb 19, 1993

8/020306

Edgar M. Williams - Palo Alto CA
Peter G. Bischoff - Cupertino CA
Daniel A. Nepela - San Jose CA

Read-Rite Corporation - Milpitas CA

G11B 5147

360126

A thin film magnetic head is fabricated having soft metal layers of 0. 25 to 1 micron thickness disposed on each side of the first and second magnetic layers of Permalloy forming the magnetic yoke. The soft layers are formed between the ceramic substrate and the first Permalloy layer, between the first Permalloy layer and the insulation surrounding the electrical coil of the head, between the insulation and the second Permalloy layer, and between the second Permalloy layer and the insulating overcoat of the head. The soft metal has a coefficient of thermal expansion between that of the Permalloy and that of the ceramic substrate and insulation materials. In this way, stress buffers are provided to minimize the mismatch and thermal stress transfer between the Permalloy and the other materials of the adjacent layers, resulting in improved domain stability and a significant reduction in popcorn noise.

4694368, Sep 15, 1987

Jan 10, 1986

6/817621

Peter G. Bischoff - Cupertino CA
David J. Rauch - Milpitas CA
Vincent D. Retort - Cupertino CA
John R. Osborne - Saratoga CA

Read-Rite Corporation - Milpitas CA

G11B 531
G11B 517

360126

A thin film magnetic head is made with a center-tapped coil structure formed of three layers of coils. The middle coil is configured to be bifilar. When recording data on a magnetic medium, current flows through one-half of the bifilar coil and through one adjacent coil to create positive transitions, and for negative transitions, current flows through the other half of the bifilar coil and through the other adjacent coil. When reading the data that is recorded on a magnetic medium, all turns of the entire coil configuration operate for transducing the data.

5255142, Oct 19, 1993

Apr 19, 1993

8/047309

Edgar M. Williams - Palo Alto CA
Peter G. Bischoff - Cupertino CA
Shin-ichi Akoh - Hirakata, JP

Read-Rite Corp. - Milpitas CA

G11B 5127
G11B 5147

360126

A thin film magnetic head is fabricated with a yoke structure, including P1 and P2 magnetic layers, having a width in the range of about 5 to 58 microns, preferably about 30 microns. The very narrow width minimizes popcorn noise, improves high frequency response and affords increased head circuit efficiency.

5327310, Jul 5, 1994

Jun 25, 1992

7/904033

Peter G. Bischoff - Cupertino CA
Chak M. Leung - Palo Alto CA
Stephen S. Murray - Fremont CA

Read-Rite Corporation - Milpitas CA

G11B 560

360103

A thin film magnetic head assembly useful for contact recording in a disk drive comprises an air bearing slider formed with only a single air bearing rail. The slider is substantially L-shaped having a leg portion on which a pedestal with an air bearing surface is provided. A wear pad is formed on the pedestal and encompasses the pole tips and transducing gap of the transducer. The wear pad makes contact with the magnetic disk during operation of the disk drive. The small area of the wear pad makes minimal contact with the surface of the magnetic disk so that frictional effects are significantly reduced thereby extending the wear life of the magnetic head. An alternative embodiment of a contact head slider uses a tripad design wherein the front pads fly relative to the disk and the rear pad which supports the transducer is in contact with the rotating disk during operation of a disk drive.

4517616, May 14, 1985

Mar 28, 1983

6/479224

Peter G. Bischoff - Cupertino CA

Memorex Corporation - Santa Clara CA

G11B 516

360126

The subject invention relates to the fabrication of metal oxide patterns on a substrate adapted for use with thin film magnetic heads. The metal oxide pattern has a precisely defined geometry including nearly vertical side walls, for minimizing read/write errors. In addition, a filler material formed from a non-magnetic, non-metallic compound is provided on the substrate in a pattern complimentary to the metal oxide pattern. In accordance with the subject invention, the top surface of the metal oxide pattern and the filler material are co-planar. By this arrangement, subsequent layers may be uniformly deposited without discontinuities. The subject method includes a plurality of distinct masking and etching steps in order to achieve the desired result.

4454014, Jun 12, 1984

Jan 3, 1983

6/455367

Peter G. Bischoff - Cupertino CA

Memorex Corporation - Santa Clara CA

C23C 1500
C25F 300
C25F 500

20412965

A method for fabricating a metallic pattern on a substrate is disclosed. The method consists of depositing an adhesive and/or plating base material on a substrate upon which a narrow self-supporting border of photoresist is applied. An anodic layer is then deposited and the photoresist removed. The adhesive and plating base material is etched in those areas previously covered by the photoresist and fresh photoresist applied to encapsulate those areas of the anodic layer which form the final pattern of interest. The unwanted anodic material is then etched and the photoresist removed.

4436593, Mar 13, 1984

Jul 13, 1981

6/282540

John R. Osborne - Saratoga CA
Peter G. Bischoff - Cupertino CA

Memorex Corporation - Santa Clara CA

G11B 542

204 15

A method is disclosed for precisely aligning the pole tips of a thin film magnetic head. Two separate metallic layers, such as Permalloy (Ni-Fe alloy) are separated by a layer of insulating material such as silicon dioxide or AL. sub. 2 O. sub. 3 which will serve as the insulative spacer of the final magnetic head. A photo-resist is applied to the surface of the top metallic layer in an imagewise configuration to establish the shape of the top pole. The top pole is then etched and the photo-resist removed. The top electrode is then encapsulated with a protective metal and is used as a mask during the chemical etching of the insulative layer, the bottom electrode being used as an etch stop. This integral structure is then used as a mask during the chemical etching of the bottom electrode, resulting in pole tips which are precisely aligned.