International Business Machines Corporation

Steven Magdo

Ingrid E Magdo

Glenn E Holmes

Guido Albert Lemke

William J Nestork

Raymond J Ferreri

Donald R Barbour

An automated, custom personalization process for generating integrated gate array chips is defined which enhances yield and reliability potential. Unused data provided in the general purpose design is deleted through a selective detection procedure based on circuit utilization.

Method of integrated circuit chips design

A corner test structure for multi-layer thin-film modules. In the corner of each layer a test structure is formed as part of the process for forming the layer itself. This corner test structure is designed to emulate the wiring pattern of the layer itself in terms of density and pattern. Each test site also includes vias for forming, in combination with vias from preceding and succeeding layers, via chain which emulate the via chains extending through the active wiring region of the module itself. Each test site structure includes a large array of test pads only a few of which are used at any given layer. The entire test pad array of each level is connected by vias to the test pattern on adjoining levels so that a test structure pattern at a given layer may be accessed from pads at each succeeding level and from pads on the upper surface of the completed module.

Test structure for multi-layer, thin-film modules

A dielectrically isolated semiconductor device which is substantially planar can be manufactured. The structure is useable for integrated circuits wherein a significant savings in surface area can be obtained over prior techniques. The structure is particularly useful for bipolar integrated circuits wherein a semiconductor substrate with an epitaxial layer thereon contains a buried region partially in the substrate and in the epitaxial layer. The emitter and base regions are located in the epitaxial layer above the buried region. The dielectrically isolating region surrounds the emitter and base region at the surface and extends to a depth wherein it intersects with the buried region to fully isolate the device. The buried region is connected as the collector element of the transistor.

Dielectric isolation for high density semiconductor devices

A dielectrically isolated semiconductor device can be manufactured. The structure is useable for integrated circuits, including field effect and/or bipolar transistors, wherein a significant savings in surface area and reduction in capacitances can be obtained over prior techniques. The method involves forming a layer of dielectric material upon a semiconductor body, having a diffused region where a bipolar device is to be formed, and then forming an opening in the layer to expose a part of the surface of the diffused region of the semiconductor body. An epitaxial layer of silicon is deposited on top. Single crystal silicon will grow over the exposed silicon area and if a diffused region is present in the substrate a pedestal will outdiffuse through the same area from the buried diffused region. Polycrystalline silicon will grow on top of the dielectric material. The pedestal is formed in a single crystal epitaxial layer of another impurity type. Two other active elements of a bipolar transistor, such as the emitter and intrinsic base regions, are then formed in the same single crystal epitaxial layer while the inactive area, such as the extrinsic base, is formed in polycrystalline silicon. A reach through is made through the dielectric layer to the third element of the transistor, that is collector region.

Dielectrically isolated semiconductor devices

An improved high performance semiconductor package assembly for interconnecting a plurality of integrated circuit devices having a multilayer substrate with internal wiring including signal wiring and external signal and power connections, a plurality of integrated circuit semiconductor devices supported on the top surface of substrate in electrically connected operative relation, the improvement being a power supply distribution system for providing electrical supply voltages to the devices from the power connections consisting of radial waveguide structure including parallel waveguide planes with a low input impedence to reduce switching noise, the waveguide planes located between the signal fan-out wiring and internal wiring metallurgy and connected in common to all of the plurality of devices.

High performance semiconductor package assembly

Structure: An integrated circuit structure with full dielectric isolation comprising a supporting substrate having a planar surface of dielectric material and a semiconductor layer on said dielectric surface which forms a planar interface with the surface. Regions of oxidized silicon extend through the layer from said interface, surrounding and dielectrically isolating pockets of silicon in the layer; the oxidized silicon regions extend to the upper surface of the semiconductor layer where they are substantially co-planar with the silicon pockets. The devices of the integrated circuit are formed in said silicon pockets. Method: The structure is fabricated by a novel method wherein a lightly doped silicon layer is deposited on a highly doped silicon substrate; surrounding oxidized silicon regions are then formed by selectively thermally oxidizing portions of the silicon layer to form oxide regions which are co-extensive with the oxidized areas and, thus, are co-planar with the remaining silicon pockets at both surfaces of the layer; a member having a dielectric surface interfacing with the silicon layer is formed, and the silicon substrate is removed by preferential electrochemical anodic etching to leave the silicon layer having the oxidized regions surrounding spaced silicon pockets mounted on said member.

Integrated circuit structures with full dielectric isolation and a novel

In the fabrication of semiconductor integrated circuits, a method is provided for forming a self-supporting silicon mask and a further method is provided for utiliziing such a self-supporting separable silicon mask to perform various masking steps in the integrated circuit fabrication. The mask is formed by forming, at a surface of a planar silicon substrate, a silicon layer having a higher concentration of conductivity-determining impurities than the substrate beneath the layer, applying to selected portions of the other surface of the substrate an etchant which preferentially etches silicon having lower concentrations of conductivity-determining impurities to thus etch out preferentially selected portions of the substrate to form at least one recess extending through the substrate to said silicon layer, and then etching from the surface of said silicon layer opposite the substrate recess to form patterns of openings extending through the silicon layer to said substrate recess. The seperable self-supporting silicon mask thus formed is then placed on the surface of an integrated semiconductor circuit member so that the opposite surface of the silicon layer interfaces with the integrated circuit member surface. Then, the masked semiconductor member may be subjectd to any conventional integrated circuit fabrication step which alters the characteristics of the portions of said member surface exposed in said pattern of mask openings; such fabrication steps include introduction of impurities, etching as well as lift-off deposition of metallic and non-metallic patterns. Upon the completion of the step or steps, the self-supporting silicon mask is separated from the integrated circuit member.

Method for making a silicon mask

An integrated circuit chip carrier with multi-level metallurgy, in which the effects of the metallurgy in causing elevation irregularities at the various levels of the structure are minimized, is produced by a method wherein a first plurality of levels of metallization patterns respectively separated by layers of dielectric material are first formed on a planar primary layer supported on a temporary substrate having a chemical etchability different from that of the layer. The primary layer is electrically insulative with respect to said metallization patterns. Then, a supporting layer is formed on the uppermost covering layer, after which the substrate is removed with a chemical etchant which preferentially etches the substrate away from the insulative layer. Next, an opposite plurality of levels of metallization patterns are formed on the side of the insulative layer opposite to the first formed metallization patterns. These opposite metallization patterns are also respectively separated by covering layers of dielectric material.

Integrated circuit chip carrier and method for forming the same

A method for fabricating both bipolar as well as complementary MOS field effect transistors, i.e., BI-CMOS transistors in the same semiconductor substrate. The preferred embodiment of the method provides bipolar and CMOS transistors having breakdown voltages (BV.sub.ceo) in excess of 10 volts and CMOS devices having no latchup problems, with a minimum number of processing steps. The method also contemplates the formation of auxiliary devices such as resistors and Schottky Barrier diodes.

High performance integrated bipolar and complementary field effect

A semiconductor resistor structure for providing a high value resistance particularly adapted for space charge limited transistor applications, the resistor being fabricated in a semiconductor body having a resistivity in excess of 1 ohm cm., more preferably in semiconductor material that is nearly intrinsic. The resistor has two parallel elongated surface diffused regions in the body of an impurity similar to the background impurity of the body and having a surface concentration sufficient to provide an ohmic contact, the boundaries of said surface diffused regions defined by the interface where the impurity concentration of the diffused region is ten percent more than the impurity concentration of the background impurity of the body. In a preferred embodiment, the surface diffused regions are spaced such that the boundaries intersect with each other, and ohmic contact terminals to each of the diffused regions.

Semiconductor resistor having a high value resistance for use in an

In the fabrication of integrated circuits, a method is provided for forming masking structures comprising silicon nitride which avoids the stresses and dislocations associated with direct silicon nitride masking as well as the 'bird's beak' problems associated with silicon dioxide-silicon nitride composite mask structures. The mask is formed by first forming a silicon dioxide mask having at least one opening through which the substrate is exposed. Then, a mask comprising silicon nitride is formed on the first mask; this mask has at least one opening laterally smaller than the openings in the first mask and respectively in registration with at least some of the openings in said first mask. Thus, the second mask contacts and covers a portion of the exposed silicon substrate under each of the registered openings. The masked silicon substrate is subjected to a processing step such as oxidation, etching or diffusion which alters the characteristics of those portions of the silicon substrate remaining exposed. During this processing step a second mask serves as a barrier mask.

Method for forming masks comprising silicon nitride and novel mask

A space-charge-limited (SCL) transistor is utilized as a photo-transistor. The preferred embodiments feature a base diffusion which is shallower than the standard SCL structure and a base geometry for increased light collection while maintaining the high current gain characteristic of SCL transistors.

Space-charge-limited phototransistor

A planar integrated circuit structure having a dielectrically isolated Schottky Barrier contact. The structure has pockets of silicon surrounded by isolating regions of silicon dioxide extending from a planar surface, the silicon dioxide regions and silicon pockets being substantially coplanar at said surface. A layer of dielectric material, such as silicon nitride or a composite of silicon nitride over silicon dioxide, covers the surface. There is at least one opening extending through the dielectric layer to a coincident silicon pocket; the opening has larger lateral dimensions than said pocket so as to expose the pocket and a portion of the silicon dioxide region surrounding the pocket. A metallic layer in this opening forms a Schottky Barrier contact with the exposed silicon.

Dielectrically isolated Schottky Barrier structure and method of forming

Fabricating high performance integrated bipolar and complementary field

A process for forming complete dielectrically isolated monocrystalline silicon regions on a substrate by depositing a first epitaxial silicon layer embodying an N-type impurity on a low resistivity silicon substrate embodying a P-type impurity, forming annular P-type impurity regions in the first epitaxial layer, depositing the second epitaxial layer embodying an N-type impurity on the first epitaxial layer, forming annular P-type impurity regions in the second epitaxial layer in registry with the annular regions in the first epitaxial layer, converting the silicon substrate and the annular P-type regions in the first and second epitaxial layers into porous silicon material by an anodic treatment carried out in an aqueous solution of hydrofluoric acid, and oxidizing the porous silicon material to form silicon oxide. A semiconductor structure having a backing substrate of silicon oxide with monocrystalline silicon islands embedded therein. A preferred embodiment includes low resistivity regions that extend through the substrate.

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Hopewell Junction, NY, United States of America

Steven Magdo