Browse Prior Art Database

Fabrication of a Silicon Knife for Use in Biological Studies

IP.com Disclosure Number: IPCOM000041247D
Original Publication Date: 1987-Dec-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Cuomo, JJ: AUTHOR [+2]

Abstract

A technique is described whereby sharp and uniform silicon knives are fabricated from a single silicon wafer, so as to provide a tool for cutting micro-thin section of biological material, as used in electron and X-ray microscopy.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 78% of the total text.

Page 1 of 1

Fabrication of a Silicon Knife for Use in Biological Studies

A technique is described whereby sharp and uniform silicon knives are fabricated from a single silicon wafer, so as to provide a tool for cutting micro-thin section of biological material, as used in electron and X-ray microscopy.

In prior art, knives with glass cutting edge have been cleaved, in that the sharpness of the cutting edge was not predictable and required several attempts to produce a knife with a sharp cutting edge. Also, the knife had to be used within a short period of time, since it would quickly become dull. The silicon knife, described herein, provides a fabrication process that will eliminate the problems inherent in the glass knives. Also, several dozen knives may be fabricated at the same time, all with the same degree of sharpness, and knives will preserve that sharpness.

First, single crystal, 100 orientation, silicon wafers are thermally oxidized. Openings in the oxide are produced by photolithography, as shown in Fig. 1, to produce an oxide pattern. The oxide pattern is transferred into the silicon wafers through a process of anisotropic etching, using any anisotropic etchant, so as to produce the pattern as shown in Fig. 2. The knife edge is formed at the intersection of the 111 plane and the 100 back surface. The angle formed is approximately thirty-five degrees. This is seventeen degrees sharper than the knives produced with glass edges. Next, the knives are diced from the wa...