Patent · US Expired

Metal trim mirror for optimized thin film resistor laser trimming

US6919984B2 · kind B2 · utility

2Cited by
3References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 4, 2003
Grant dateJul 19, 2005
Priority date
Expiry dateAug 4, 2023

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K26/064
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A device and a method of forming the device are disclosed. The device includes a reflector, a first dielectric layer disposed on the reflector, and a thin film resistor disposed on the reflector. The reflector acts as a barrier between the thin film resistor and an underlying dielectric layer which may have a non-uniform thickness. Thus, the thickness control and uniformity of the dielectric layer underlying the reflector does not affect the laser trimming of the thin film resistor. In addition to serving as a barrier, the reflector reflects the trimming laser energy back towards the thin film resistor, thereby improving the efficiency of the laser trimming of the thin film resistor. Furthermore, the thickness of the first dielectric layer situated below the thin film resistor and above the reflector can be easily controlled to substantially optimize the laser trimming efficiency of the thin film resistor.

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