US Government As Represented by the Secretary of the Army

Phillip R Boyd

John H Dinan

Barbara E Sumner

Michael Martinka

Gary K Green

Andrew J Stoltz, Jr

Leo Anthony Almeida

J David Benson

Andrew W Kaleczyc

A lithographic imaging method of the present invention includes the initial step of providing a substrate made from Mercury, Cadmium and Telluride materials (HgCdTe). The HgCdTe substrate is coated with a diazonaphthoquinone (DNQ) Novolak photoresist material to establish an imaging medium. The imaging medium is exposed to an image pattern and then developed in a tetra-methyl ammonium hydroxide (TMAH) solution. The TMAH solution includes a fullerene (C) material dissolved therein to retard the subsequent etching of the imaging medium. The incorporation of fullerene into the photoresist material indirectly via the developing solution avoids the solubility and ultraviolet (UV) absorbance disadvantages inherent in adding fullerenes directly to the photoresist prior to placement on the substrate. After development, the imaging medium is etched to transfer the recorded image pattern to the substrate. The fullerene cooperates with the photoresist material to slow the etching process, which allows for a highly reticulated HgCdTe detectors and IR images having greatly enhanced resolution.

Fullerene addition in photoresist via incorporation in the developer

The invention provides a test system and method using E-Beam techniques to characterize LSI photodiode arrays in both their electrical and optical properties.

High speed semiconductor characterization technique

A method of preparing a mercury cadmium telluride substrate with a cadmium elluride surface of less than 200 .ANG. to yield a surface exhibiting improved quality and smaller variation in the x-valve of a Hg.sub.1-x Cd.sub.x Te substrate for passivation and processing of the CdTe processed surface. The method comprises the steps of etching said Hg.sub.1-x Cd.sub.x Te substrate with a bromine methanol or bromine-DMF etch, quenching the substrate in methanol or DMF until the bromine is removed and rinsing in acetone and methanol to remove soluble residuals and drying immediately, coating said substrate with CdTe layer of about 1000 .ANG., polishing the processed CdTe layer by a contactless polishing means using a polishing solution of 50% ethylene glycol and 50% mixture of 2% bromine and 98% methanol wherein said CdTe layer is polished down to generally less than 200 .ANG. according the monitored condition of the CdTe layer, and repeating the quenching, rinsing and drying steps to remove all bromine and soluble residuals.

Method of preparing a mercury cadium telluride substrate for passivation

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Upper Marlboro, MD, United States of America

Phillip R Boyd