International Business Machines Corporation

Hans Wimpfheimer

Majid Ghafghaichi

Hormazdyar M Dalal

Lucian A Kasprzak

Theodore H Baker

Richard Charles Stevens

A silicon semiconductor device having contacts which include tantalum. The tantalum is useful in particular for fabricating Schottky barrier diodes having a low barrier height. The method includes: precleaning the silicon substrate prior to depositing the tantalum; depositing the tantalum at low pressure and low substrate temperature to avoid oxidation of the tantalum; and sintering the contact to reduce any interfacial charges and films remaining between the silicon and tantalum. When a metal which reacts with silicon during processing, such as aluminum, is used as interconnection metallurgy, a layer of chrome must be deposited between the tantalum and aluminum.

Method for fabricating tantalum semiconductor contacts

Tantalum semiconductor contacts and method for fabricating same

A method of planarizing an electrically insulative layer formed over a non-planar integrated circuit substrate having raised portions. After the electrically insulative layers are deposited over such substrate, the layer has elevations corresponding to the underlying raised portions of the substrate. A masking layer is formed on the electrically insulative layer having at least one opening therethrough coincident with an elevation in the insulative layer; this opening has smaller lateral dimensions than the coincident elevation, thereby facilitating alignment. The elevation in the insulative layer exposed in said at least one opening is then etched to the level of the unelevated portion of the layer, and the insulative layer is then resputtered for a period of time sufficient to planarize the remainder of such etched elevation to the level of the unelevated portions.

Planarizing insulative layers by resputtering

Growing community of inventors

Poughkeepsie, NY, United States of America

Hans Wimpfheimer