Lucent Technologies Inc.

At+t Corp.

Rajiv N Pathak

Keith Wayne Goossen

John E Cunningham

James Albert Walker

William Y Jan

An in-situ method is disclosed for highly accurate lattice matching using reflection high energy electron diffraction dynamics. The method includes the steps of providing a substrate of a first semiconductor material and initiating growth of a second semiconductor material thereon. The oscillation amplitude of intensity I of waveform cycles is monitored using reflection high energy electron diffraction. A maximum intensity I.sup.+ and a minimum intensity I.sup.- is determined over a predetermined number of waveform cycles. The intensity drop .DELTA.I from initial reflectivity to minimum reflectivity of the waveform cycles is determined and normalized figure of merit FM is calculated for the predetermined number of waveform cycles using the relationship: ##EQU1## The fluxes of the second semiconductor material are then adjusted to maximize FM and optimize matching. A multiple quantum well light modulator is also provided including a semiconductor substrate of InP, a multiple quantum well region, disposed above the InP substrate, composed of InGaAs and having a thickness of about 4 .mu.m. The modulator is characterized by a lattice mismatch of less than 2.times.10.sup.4.

Accurate in-situ lattice matching by reflection high energy electron

A monolithically integrated, optoelectronic VLSI circuit is fabricated by growing optical devices on the compound semiconductor surface of a VLSI chip or wafer having pre-existing electronic devices formed thereon. In accordance with an illustrative embodiment of the present invention, a large array of surface normal optical modulating devices such as multiple quantum well modulators is grown on an impurity free surface of a VLSI chip having an array of FETs already provided thereon. The growth of such devices takes place at temperatures below 430.degree. C. on a compound semiconductor surface which has a highly ordered atomic structure. An optoelectronic switch constructed in this manner is capable of addressing electronic chips in systems handling 10,000 or more input/output optical beams.

Monolithically integrated VLSI optoelectronic circuits and a method of

An in-situ method is disclosed for highly accurate lattice matching using reflection high energy electron diffraction dynamics. The method includes the steps of providing a substrate of a first semiconductor material and initiating growth of a second semiconductor material thereon. The oscillation amplitude of intensity I of waveform cycles is monitored using reflection high energy electron diffraction. A maximum intensity I.sup.+ and a minimum intensity I.sup.- is determined over a predetermined number of waveform cycles. The intensity drop .DELTA.I from initial reflectivity to minimum reflectivity of the waveform cycles is determined and a normalized figure of merit FM is calculated for the predetermined number of waveform cycles using the relationship: ##EQU1## The fluxes of the second semiconductor material are then adjusted to maximize FM and optimize lattice matching. A multiple quantum well light modulator is also provided including a semiconductor substrate of InP, a multiple quantum well region, disposed above the InP substrate, composed of InGaAs and having a thickness of about 4 .mu.m. The modulator is characterized by a lattice mismatch of less than 2.times.10.sup.-4.

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Matawan, NJ, United States of America

Rajiv N Pathak