Patent · US Expired

Method for etching photolithographically produced quartz crystal blanks for singulation

US5650075A · kind A · utility

44Cited by
4References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1995
Grant dateJul 22, 1997
Priority date
Expiry dateMay 30, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10N30/082
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A method for etching (200) photolithographically produced quartz crystal blanks for singulation. First, a quartz wafer is plated on both sides with metal and subsequently coated on both sides with photoresist (202). Second, the photoresist is patterned and developed and the metal layers etched to define the periphery of a quartz blank with a narrow quartz channel exposed between the blank to be singulated and the parent quartz wafer (204). Third, the quartz channel is preferentially etched partially into the wafer along parallel atomic planes to provide a mechanically weak junction between the quartz wafer and the blank to be singulated, while the periphery around the remainder of the quartz blank is etched completely through the parent quartz wafer (206). Fourth, the photoresist layers are stripped from the quartz wafer (208). Finally, the quartz blank is cleaved substantially along the bottom of the quartz channel to singulate the crystal blank from the wafer (210).

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