PRODUCTION ENGINEERING MEASURE FOR IMPROVEMENT OF PRODUCTION TECHNIQUES TO INCREASE THE RELIABILITY FOR PNP INTERMEDIATE POWER SILICON PLANAR SWITCHING TRANSISTORS INCLUDING 2N3502.
Abstract
Thorough evaluation of the test results, accumulated during the operation of the test-masking line built by Fairchild, proved the feasibility of the mechanized semiautomatic masking process. However, a modification of the mechanical concept was necessary for the post exposure part. Through a long term systematically determined evaluation program, it was found that improvements had to be made in certain areas of the Optical Alignment Jig. The areas were in the Microscope Assembly, Light Source Assembly and Chuck and Positioner Assembly. A preliminary survey of the 2N3502 devices was made. The survey indicated that Beta variation is most pronounced in the vertical direction of a wafer; it is maximum on top of the wafer and minimum at the bottom. This directional, rather than random variation of Beta, indicated several possible causes, some of which have been investigated. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 31, 1965
- Accession Number
- AD0617893
Entities
People
- J. C. Diepeveen
- R. C. Dorilag