Infrared Photography of Micro-Circuit Hot Spots
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-08
This article describes a method of using infrared sensitive photographic film for locating integrated circuit hot spots. Small areas dissipating as little as 20 mw have been identified by this method. Resolution is approximately one micron. The equipment requirements include only an optical microscope with camera and inexpensive film development and electrical support equipment. The infrared radiation generated by the hot spots must have some portion of its energy with wavelengths less than 1 um. This is necessary to achieve high resolution and because infrared film is not sensitive to wavelengths longer than 1 um. To obtain these short wavelengths, the integrated circuit must be heated until the hot spot temperature is at least 250ŒC. Following are the relevant process details: 1. The chip must be exposed.