Method of producing a laser trimmable thin film resistor in an integrated circuit
US6326256A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1999 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Sep 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/474
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A thin film resistor processing flow solves the problem of accurately incorporating the resistor (80) to be trimmed in an optimized multilayer stack (60,70). This is achieved by measuring the total thickness of the dielectric stack (60) between the silicon substrate and the top of the dielectric stack just prior to the formation of the thin film resistor (80). Then, the thickness of the dielectric stack (60) is adjusted (60+70) to be an odd integer number of laser quarter wavelengths. The thin film resistor (60) is then formed and overlying dielectric (120) is deposited. The thickness of the overlying dielectric (120) may likewise be adjusted (120+130) to be an odd integer number of laser quarter wavelengths.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.