Method of producing ultrafine silicon tips for the AFM/STM profilometry

US5242541A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Thomas Bayer · Igersheim, DE
• Johann Greschner · Neckartenzlingen, DE
• Yves Martin · Ossining, US
• Helga Weiss · Eppelheim, DE
• Hemantha K. Wickramasinghe · Chappaqua, US
• Olaf Wolter · Aidlingen, DE

Key dates

• Filing date: Aug 16, 1990
• Grant date: Sep 7, 1993
• Expiry date: Aug 16, 2010

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S977/878
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method is described for producing ultrafine silicon tips for the AFM/STM profilometry comprising: PA0 1. providing a silicon substrate and applying a silicon dioxide layer thereto; PA0 2. producing a mask in said silicon dioxide layer by photolithography and wet or dry etching; PA0 3. producing a tip shaft by transferring the mask pattern, produced in step 2, by reactive ion etching into the silicon substrate; PA0 4. thinning the shaft and forming a base by isotropic wet etching; and PA0 5. removing the mask by etching. The resulting tip shaft with a rectangular end may be pointed by argon ion milling. In a second embodiment there is an anisotropic wet etching step, prior to step 5, through the intact silicon dioxide mask, producing a negative profile of the shaft immediately below the mask. After this etching step the mask is removed by etching.