Patent · US Expired

Method of verifying a mask for a mask ROM

US6773937B1 · kind B1 · utility

12Cited by
1References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 15, 2003
Grant dateAug 10, 2004
Priority date
Expiry dateSep 15, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B20/38
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

In a method to verify a mask for a mask ROM, a serial of random codes that are exclusive to each other are implanted into a plurality of wafers manufactured by a same process with the mask or a plurality of die regions in a single wafer manufactured by a same process with the mask, and then the test results derived from the implanted wafers or die regions are compared to determine if the mask is defective.

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