Hermetic RF connection for on-wafer operation
View Patent ↗A hermetically sealed link for low loss coaxial airline connection between the wafer probe and the RF connector of an external instrument with 30 or 45 degrees wafer probes allows continuous, micro-positioner controlled, 3 axis horizontal and vertical probe movement. A flexible sealing ring ensures airtight and/or RF-EMI shielded operation. A metallic or plastic collar ensures wafer testing under EMI, airtight or high temperature conditions.
1. An adjustable sealed link penetrating into a RF-EMI and thermally isolated chamber of a wafer test station for connecting load pull tuners with wafer probes,
said chamber having top cover, bottom plate and sidewalls, and holding a semiconductor wafer on its bottom plate,
said link comprising,
a section of low loss coaxial airline,
a vertical cylinder, and
a plate covering an opening in the top cover of the chamber;
wherein
the airline traverses the cylinder diagonally from top to bottom towards the wafer probe;
the cylinder slide-fits and slides vertically inside a hole in the covering plate;
the covering plate slides on the top cover of the chamber;
and wherein
all sliding contacts are hermetic, and RF-EMI shielded.
2. The link of claim 1 ,
wherein
the cylinder slides inside a surrounding collar which is mounted vertically on a secondary plate attached to the covering plate.
3. The link of claim 1 ,
wherein
the cylinder slides inside a RF-EMI sealing flexible O-ring, which is inserted between the cylinder and the hole in the covering plate.
4. The link of claim 1 ,
wherein
the cover plate slides on a RF-EMI-shielding gasket placed between the bottom of the cover plate and the underlying top of the chamber.
5. The link as in claim 2 ,
wherein
the cylinder glides vertically, slide fitting, inside the collar.
6. The link as in claim 2 ,
wherein
the cylinder is attached to a handle,
and wherein
the handle is attached to an external 3-axis (X-Y-Z) micro-positioner, which is attached to the platform of the wafer-probe station.