Method of making silicon capacitive pressure sensor with glass layer between silicon wafers

• US 4,773,972 A
• Filed: 10/30/1986
• Issued: 09/27/1988
• Est. Priority Date: 10/30/1986
• Status: Expired due to Term

• Current Assignee: University of Michigan
• Original Assignee: Ford Motor Company
• Inventors: Mikkor, Mati
• Primary Examiner(s): Ball, Michael W.
• Assistant Examiner(s): AFTERGUT, JEFFRY H
• Application Number:
  US06/924,720
• Time in Patent Office: 698 Days
• Field of Search: 156/89, 361/280, 361/283, 73/718, 73/724, 29/590, 29/29.2, 29/610, 29/5 G, 437/14, 437/901, 437/921, 437/203, 437/954, 204/16, 148/DIG. 12
• US Class Current: 156/89.15
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 2207/096 through the substrate
• CPC Class Codes: B81C 1/00301 Connecting electric signal lines from the MEMS device with external electrical signal lines, e.g. through vias
• CPC Class Codes: G01B 2210/64 Interconnection or interfacing through or under capping or via rear of substrate in microsensors
• CPC Class Codes: G01L 9/0073 using a semiconductive diaphragm
• CPC Class Codes: Y10S 148/012 Bonding, e.g. electrostatic for strain gauges
• CPC Class Codes: Y10T 29/49103 Strain gauge making

Abstract

A method of bonding two silicon wafers each having a capacitive plate. Two highly-doped electrically semiconductive feedthrough paths are formed through one wafer, each path contacting one of the capacitive plates. A glass layer is formed on one of the silicon wafers where bonding is desired between the two wafers. The glass layer is anodically bonded to the other of the silicon layers.

Claims