The invention is for the formation of multilayer circuit boards where layers are formed sequentially using selective plating techniques and photoimaging of permanent dielectric materials to achieve fine line resolution and interconnections between circuits. The invention permits the sequential formation of multilayers of higher density using photoimaging techniques.

Method for manufacture of multilayer circuit board

THIS SPECIFICATION DISCLOSES A METHOD OF FABRICATING AN INTEGRATED CIRCUIT CHARACTERIZED BY ELECTRONIC COMPONENTS BEING FORMED IN A POLYCRYSTALLINE SEMICONDUCTOR, SUCH AS SILICON OR GERMANIUM, DEPOSITED AT LESS THAN 900*C. AND AT A RATE OF LESS THAN ONE MICRON PER MINUTE AND OVERLYING AN ISOLATION LAYER COVERING COMPONENTS FORMED IN A BASE REGION OF MONOCRYSTALLINE SEMICONDUCTOR MATERIAL. THE COMPONENTS IN THE POLYCRYSTALLINE SEMICONDUCTOR MAY EMPLOY JUNCTIONS AND MAY BE ACTIVE OR PASSIVE. MORE THAN ONE LAYER OF POLYCRYUSTALLINE SEMICONDUCTOR AND MORE THAN ONE ISOLATION LAYER MAY BE EMPLOYED.

Bi-layer insulation structure including polycrystalline semiconductor material for integrated circuit isolation

A method for mounting semiconductor chips to printed circuitry via conductive columns which extend through the dielectric substrate and electrically communicate with a predetermined pattern of conductive leads on the opposite surface of the substrate. Printed circuitry useful for practicing the method is also provided.

Circuitry and method

A multi-layer printed circuit board with self-contained printed resistors includes an undercoat layer made of an insulating material and formed on an outermost conductor circuit at least except for a ground portion of the outermost conductor circuit; an electro-magnetic wave shield layer made of a cured copper paste and formed on the undercoat layer and the ground portion of the outermost conductor circuit so as to cover a generally entire surface of the outermost conductor circuit; and protective overcoat covering an outer surface of the shield layer.

Printed circuit board having electromagnetic wave shield layer and self-contained printed resistor

There is disclosed a magnetic field generating device for use in a magnetooptical recording apparatus of a magnetic field modulation method. The device includes a planar spiral coil, of which coil pitch is smaller in the peripheral area than that in the central area thereof, thus realizing a relatively wide area of magnetic field of uniform intensity, with a low inductance. Because of the planar structure, the device can be positioned very close to the recording medium, and can achieve the high speed switching required in the magnetic field modulation method, without a large power source.

Magnetic field generating device

Process for manufacturing multilayer film circuits

A method for fabricating an array of read-write heads for a magnetic storage means, such as a disk or drum, is disclosed. Each head is comprised of a flux-carrying means, such as a gapped magnetic loop inductively coupled to a flux-producing means, such as a pair of coils. The coils, together with a portion of the associated addressing circuitry, are formed on a high resistivity substrate. The halves of the magnetic loops that lie on opposite sides of the coil assembly are fabricated in the relative position on two separate assemblies. The two assemblies are then bonded to opposite sides of the coil assembly so that the halves of the magnetic loops mate through holes in the substrate to form the complete gapped magnetic loops. The excess material of the assemblies is then cut away as required to leave magnetically isolated magnetic loops and the associated coils embedded within a solid body. The sensing gaps of the magnetic loops are formed by vacuum depositing a thin layer of nonmagnetic material on a face of one ferrite part, disposing a second ferrite part against the thin nonmagnetic layer and bonding the two ferrite parts together, taking a section of two ferrite parts normal to the nonmagnetic layer, and bridging the nonmagnetic layer with a third ferrite part to complete the magnetic loop. The loop assemblies may be formed by cutting grooves in the faces of ferrite blocks to form a number of ferrite mesas corresponding to the number of read-write heads. The grooves are then filled with a nonmagnetic material to magnetically isolate the ferrite mesas. The loop assemblies are then bonded to opposite sides of the coil assembly before being separated from the ferrite block. Alternatively, the ferrite assembly may be formed by laminating a layer of ferrite material, or two layers of ferrite material separated by a thin layer of nonmagnetic material for forming a sensing gap, between two layers of nonmagnetic material, slicing the layers in a plane normal to the layers to produce a number of slices each having a strip of ferrite disposed between strips of nonmagnetic material, then laminating these slices such that each strip of ferrite is isolated by nonmagnetic material. This laminated structure is again sliced normal to the last laminating joints to produce slices having individually isolated ferrite islands extending normal to the slice. Each ferrite island is then incorporated into a magnetic loop.

Method for fabricating magnetic read-write head array and product

1,244,011. Superconductor devices. TEXAS INSTRUMENTS Inc. 20 Sept.. 1968 [23 Oct., 1967], No. 44737/68. Heading H1K. A superconductor device includes a granular layer of particulate grains of superconductor separated by insulating barriers of the oxide of the material of the grains thin enough to permit electron pair tunnelling therethrough. In a first embodiment, Fig. 2 (not shown), a gate conductor has a particulate portion forming an array of Josephson junctions separated by a thin insulating layer, forming a further Josephson junction, from a thick superconductor member. A control conductor crosses the particulate portion and when energized interrupts the coherence effects in the Josephson junctions which switch to the "normal" (quasi-particle tunnelling) state. The device may be formed by depositing a ground plane on a glass substrate, insulating with a layer of photo-resist, depositing a thick Sn member, oxidizing the surface, depositing a Pb gate conductor and anodizing the portion above the Sn member to form the particulate portion and finally depositing insulation and a control conductor. A cryotron may comprise a particulate member being an array of Josephson junctions, Fig. 10 (not shown). The particulate member may be formed of Ta particles oxidized by glow discharge and allowed to settle on the substrate. Alternatively a continuous film having bumps, Fig. 11 (not shown) may be deposited and the surface anodized to form particles separated by thin oxide layers to form Josephson junctions, Fig. 12 (not shown). Such a cryotron emits radiation due to the AC Josephson-effect and may be placed in a waveguide. When suitably biased the device may also detect radiation. Particulate Josephson junction cryotrons may be utilized in flip-flop cell in the form of a loop in which a persistent current is stored, the direction of current flow indicating the state of the cell. Non-destructive read-out is achieved by sense lines incorporating Josephson junction cryotrons the states of which are determined by the direction of the current flow in the adjacent arm of the loop relative to a current in sense bias lines extending parallel to the arms of the loop, Figs. 7 to 9 (not shown).

Joe T Pierce

Papers

Process for manufacturing multilayer film circuits

Method for fabricating magnetic read-write head array and product

Superconductive barrier devices

Cryogenic semiconductor devices

Process for making thin film circuit devices