Patent · US Expired

Lapping method and system for compensating for substrate bow

US5967878A · kind A · utility

7Cited by
14References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 1997
Grant dateOct 19, 1999
Priority date
Expiry dateApr 25, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/398
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method and system is disclosed for lapping row edges of a substrate work piece with a flat lapping element. The substrate work piece comprises a section of wafer having parallel aligned multiple row edges to be individually lapped. The wafer has different bow characteristics imparted to different substrate work piece. The bow characteristic of the substrate work piece to be lapped is determined, load points are selected on the work piece which will counteract the bow characteristic, and a pusher with push pads located at the selected load points pushes the work piece at those load points so that the pushing flexes the substrate work piece to counteract the bow characteristic to lap the row edge. Upon completion of the lapping step, the row having the lapped row edge is sliced from the work piece to form a new row edge parallel to the lapped row edge, and, repeating the lapping process, the work piece is pushed by the push pads at the same selected load points, whereby, as the substrate is shortened, making said bow characteristic more pronounced, the pushing at the selected load points provides greater flex of the work piece to counteract the more pronounced bow.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.