Method of making semiconductor device

• US 4,472,239 A
• Filed: 07/08/1983
• Issued: 09/18/1984
• Est. Priority Date: 10/09/1981
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Higashi, Robert E., Johnson, Robert G.
• Primary Examiner(s): Powell, William A.
• Application Number:
  US06/512,079
• Time in Patent Office: 438 Days
• Field of Search: 156/647-649, 156/657, 156/659.1, 156/661.1, 156/653, 156/662, 430/313, 430/316, 430/312, 430/318, 427/88-90, 422/95, 422/97, 422/98, 29/580, 29/591, 29/573, 357/55, 357/68, 357/69, 357/71, 73/23, 73/704, 73/723, 73/778
• US Class Current: 438/49
• CPC Class Codes: G01F 1/6845 Micromachined devices
• CPC Class Codes: H10N 19/00 Integrated devices, or assemblies of multiple devices, comprising at least one thermoelectric or thermomagnetic element covered by groups H10N10/00 - H10N15/00

Abstract

A semiconductor device comprising a semiconductor body having a depression formed into the first surface of the body. The device further comprises member means comprising a thermal-to-electric or static electric element, the member means having a predetermined configuration suspended over the depression. The member means is connected to the first surface at least at one location, the depression opening to the first surface around at least a portion of the predetermined configuration. The depression provides substantial physical and thermal isolation between the element and the semiconductor body. In this manner, an integrated semiconductor device provides an environment of substantial physical and thermal isolation between the element and the semiconductor body.

Claims

1. A method of fabricating a semiconductor device comprising member means having a predetermined configuration suspended over a depression etched into a first surface of a semiconductor body, the member means being connected to the first surface at least at one location, the depression opening to the first surface around at least a portion of the predetermined configuration, the method comprising the steps of:

providing a semiconductor body with the first surface having a predetermined orientation with respect to a crystalline structure in the semiconductor body;

applying a layer of material of which the member means is comprised onto the first surface;

exposing at least one predetermined area of the first surface, the exposed surface area being bounded in part by the predetermined configuration to be suspended, the predetermined configuration being oriented so that an anisotropic etch placed on the exposed surface area will undercut the predetermined configuration in a substantially minimum time; and

applying the anisotropic etch to the exposed surface area to undercut the member means and create the depression.

3. The method of claim 1 or 2 wherein:

the semiconductor body comprises (100) silicon having a (100) plane and a [110] direction;

the first surface of the semiconductor body is substantially parallel to the (100) plane; and

the predetermined configuration is oriented at a non-zero angle to the [110] direction.

4. The method of claim 3 wherein the predetermined configuration comprises a substantially straight edge which is oriented at the non-zero angle.

5. The method of claim 4 wherein the non-zero angle is substantially 45 degrees, whereby the member means will be undercut with maximum efficiency.

6. The method of claim 3 wherein the predetermined configuration has an axis which is oriented at the non-zero angle.

7. The method of claim 6 wherein the non-zero angle is substantially 45 degrees, whereby the member means will be undercut with maximum efficiency.

8. The method of claim 3 wherein the non-zero angle is substantially 45 degrees, whereby the member means will be undercut with maximum efficiency.

2. A method of fabricating a semiconductor device comprising member means having a predetermined configuration bridging a depression etched into a first surface of a semiconductor body, the member means being connected to the first surface at first and second substantially opposing ends of the predetermined configuration, the depression opening to the first surface around at least a portion of the predetermined configuration, the method comprising the steps of:

providing a semiconductor body with the first surface having a predetermined orientation with respect to a crystalline structure in the semiconductor body;

applying a layer of material of which the member means is comprised onto the first surface;

exposing first and second predetermined areas of the first surface, the exposed surface area being bounded in part by the predetermined configuration to be bridged, the predetermined configuration being oriented so that an anisotropic etch placed on the exposed surface area will undercut the predetermined configuration in a substantially minimum time; and

applying the anisotropic etch to the exposed surface area to undercut the member means and create the depression.