Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Precision-Submicron-Dimensioned Mask for X-Ray Lithography

IP.com Disclosure Number: IPCOM000044486D
Original Publication Date: 1984-Dec-01
Included in the Prior Art Database: 2005-Feb-06
Document File: 2 page(s) / 41K

Publishing Venue

IBM

Related People

Riseman, J: AUTHOR

Abstract

This article deals with the employment of "sidewall" technology to produce submicron features on a standard X-ray lithography mask. In principle, such masks would be generated by electron beam methods but submicron dimensions are still beyond this capability, primarily for economic reasons. The disclosed technique, by using the oxide that grows on the vertical walls ("sidewalls") of patterned polysilicon films, as a mask for forming submicron features on X-ray masks, overcomes this problem. X-ray masks are made by patterning a heavy metal film (such as gold) on a previously deposited X-ray transparent film (such as boron nitride (BN)) which covers a silicon wafer.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 59% of the total text.

Page 1 of 2

Precision-Submicron-Dimensioned Mask for X-Ray Lithography

This article deals with the employment of "sidewall" technology to produce submicron features on a standard X-ray lithography mask. In principle, such masks would be generated by electron beam methods but submicron dimensions are still beyond this capability, primarily for economic reasons. The disclosed technique, by using the oxide that grows on the vertical walls ("sidewalls") of patterned polysilicon films, as a mask for forming submicron features on X-ray masks, overcomes this problem. X-ray masks are made by patterning a heavy metal film (such as gold) on a previously deposited X-ray transparent film (such as boron nitride (BN)) which covers a silicon wafer. The silicon, except for a retaining ring on the periphery, is subsequently etched away, leaving a metal "absorber" pattern on the BN film, which is the transparent carrier. The essence of the disclosed procedure entails the use of "sidewall" technology, as here described, to generate the submicron dimensions called for in the manner that follows, beginning with Fig. 1. 1. A silicon wafer 2 is coated with BN in the order of a 1.0-micron thickness, upon which is deposited an "absorber" metal 4, in this case, gold, in the order of 2000-angstrom thickness. Tantalum may be used for adhesion. This is coated, in turn, with silicon nitride 5 of 1000-angstrom thickness, upon which is deposited a layer of polysilicon 6 from 3000 to 10000 angstroms in thic...