Coaxial wafer probe with tip shielding

US5565788A · kind A · utility

Assignee

• Cascade Microtech, Inc. · US

Inventors

• Jeremy Burr · Portland, US
• Gregory N. Nordgren · Wilsonville, US
• Eric W. Strid · Portland, US
• Kimberly R. Gleason · Portland, US

Key dates

• Filing date: May 12, 1995
• Grant date: Oct 15, 1996
• Expiry date: May 12, 2015

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R1/06772
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A shielded microwave probe tip assembly includes an end of a coaxial cable coupled to probe fingers forming a coplanar controlled impedance microwave transmission line where the ground probe fingers are interconnected by a shield member that is spaced apart from the signal line probe finger but is positioned between the signal line probe finger and a device under test. The shield prevents the generation of extraneous signals or parasitic coupling from the device under test which would otherwise degrade measurement accuracy.