Method for the smooth fine classification of varactor diodes

US5102818A · kind A · utility

Assignee

• Deutsche ITT Industries, GmbH · DE

Inventors

• Klaus Paschke · Bad Homburg vor der Höhe, DE
• Roland Zipfel · Schallstadt, DE

Key dates

• Filing date: Sep 13, 1990
• Grant date: Apr 7, 1992
• Expiry date: Sep 13, 2010

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/49004
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A "smooth" fine classification of varactor diodes according to their electrical parameters is achieved in the manufacturing process to provide groups of matched varactor diodes. The diodes are matched within a predetermined tolerance limit. The dice are picked up from the silicon wafer along a meander path generally perpendicular to the temperature gradient of the diffusion process steps applied to the wafer when the diodes were formed, mounted on a lead frame, bonded, encapsulated, removed from the lead frame, and measured.