Leland Stanford Junior University

Zoran Corporation

International Microelectronic Products

Levy Gerzberg

James F Gibbons

Arnon Gat

Eric R Sirkin

Ilan A Blech

Alexander B Sinar

Yosef Y Shacham

Chong-Cheng Fu

Roger D Melen

James D Meindl

A memory matrix comprises a plurality of word lines, a plurality of bit lines, and a stacked diode and voltage-variable resistor structure interconnecting bit lines to word lines. The stacked diode and voltage-variable resistor structure includes a doped region in a semiconductor substrate defining a work line, a doped polycrystalline silicon layer over said word line and forming a p-n junction therewith, and an amorphized region in the doped polycrystalline silicon layer having increased resistance over the non-amorphized portion of the doped polycrystalline silicon layer. A contact is made to the amorphized polycrystalline silicon material which preferably includes a titanium-tungsten barrier layer and an aluminum layer over the barrier layer. To improve the breakdown voltage of the diode structure, a region of opposite conductivity type is formed in the word line under the doped polycrystalline silicon layer either by out-diffusion of dopants from the polycrystalline silicon layer or by the implantation of dopant ions through the polycrystalline silicon layer into the word line.

Programmable memory matrix employing voltage-variable resistors

A voltage-programmable device in which the programming voltage V.sub.p and the 'off' resistance R.sub.i are separately controlled. The device includes a body of semiconductor material having a doped region therein, and an amorphized layer in the doped region and abutting a surface, and a surface layer in the amorphized layer with the surface layer having a resistivity higher than the resistivity of the amorphized layer prior ot programming of the device. The surface layer has a miniscule thickness (on the order of 50-150 Angstroms) and does not affect the programming of the device. Moreover, the final resistance of the programmed device is not significantly affected by the presence of the first layer. The amorphized layer is formed by ion implantation, and the or by oxygen plasma treatment.

Double layer voltage-programmable device and method of manufacturing same

A programmable read only memory (PROM) includes voltage programmable structures which are readily fabricated to provide predictable and selectable programming voltages. The resistor structure includes a body of semiconductor material having high electrical conductance and a surface contact region having a crystalline structure characterized by relatively high electrical resistance. The relatively high electrical resistance can be established by amorphotizing the surface region or by forming lattice defects in the crystalline structure such as by ion implantation. In programming the PROM, a sufficient voltage is applied across, or sufficient current is applied through, selected structures whereby the surface regions thereof are heated sufficiently to reduce the relatively high electrical resistance.

Electrically programmable read only memory

Transducer structures for use in volume flow measurements which generate a first uniform beam and a second focused beam within the uniform beam. The transducer may include concentric elements, a linear array, or combinations thereof. In a two element concentric array, a central disc generates a uniform beam and a peripheral annular element having a lens thereon defines a second focused beam within the first beam. In a linear array a plurality of juxtaposed linear elements define a scan surface and a segmented element within the linear element array defines a focused reference sample volume within the scanned surface. A concentric array having a plurality of annular elements is driven with amplitude weighting of each element in accordance with a Fourier-Bessel approximation to the desired beam pattern thereby electronically achieving ultrasonic beam width control.

Ultrasonic transducers and applications thereof

Transducer structures for use in volume flow measurements which generate a first uniform beam and a second focused beam within the uniform beam. The transducer may include concentric elements, a linear array, or combinations thereof. In a two element concentric array, a central disc generates a uniform beam and a peripheral annular element having a lens thereon defines a second focused beam within the first beam. In a linear array, a plurality of juxtaposed linear elements define a scan surface, and a segmented element within the linear element array defines a focused reference sample volume within the scanned surface. A concentric array having a plurality of annular elements is driven with amplitude weighting of each element, in accordance with a Fourier-Bessel approximation to the desired beam pattern, thereby electronically achieving ultrasonic beam width control.

Transducer structure for generating uniform and focused ultrasonic beams

A distributed resistor-capacitor device which is highly reproducible with near ideal electrical characteristics including a substrate, an insulating layer on a major surface of the substrate, and a polycrystalline semiconductor material on the insulating layer. The polycrystalline layer is the resistor and cooperates with the substrate as the capacitor. Fabrication of the device is compatible with integrated circuit fabrication and can be used with field-effect and bipolar junction transistors.

Monolithic distributed resistor-capacitor device and circuit utilizing

A programmable read only memory (PROM) includes a first plurality of conductive lines, a second plurality of conductive lines and polycrystalline silicon material therebetween. At the crossing points of the first and second plurality of lines doped regions are provided in the polycrystalline silicon in contact with a second line and which extend at least partially through the material. To provide a diode interconnect at any crossing point, the associated region is irradiated by a laser beam to either cause diffusion of dopant atoms to the underlaying conductive line or activate implanted ions, thereby electrically interconnecting the first and second lines through a diode. The PROM is readily fabricated as part of a monolithic integrated circuit or electrical array and can be programmed after completion of the fabrication process.

Read only memory and integrated circuit and method of programming by

Low resistance, doped polycrystalline semiconductor connection patterns are fabricated by scanning a doped polycrystalline layer with a laser beam thereby increasing the crystal grain size, reducing defects in the grains, increasing charge carrier mobility and as a result reducing material resistivity. Semiconductor devices having increased circuit density and speed are realized through use of laser annealed polycrystalline semiconductor resistors, contacts and interconnections.

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Palo Alto, CA, United States of America

Levy Gerzberg