Semiconductor Substrate Contact
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-05
A semiconductor substrate contact is made between a substrate and the surface of a semiconductor chip by utilizing the mechanically damaged subcollector to substrate junction around the periphery of a diced chip to establish electrical continuity. As indicated in the figure, a P-type semiconductor substrate 10 and an N type epitaxial layer 12 have an N+ subcollector region 14 interposed therebetween in chip 15. Trenches 16 and 18 filled with an insulating material, e.g., an oxide 20, extend from the surface of epitaxial layer 12 to substrate 10 through N+ subcollector region 14. An N+ reach-through region 22 passes through epitaxial layer 12 to the N+ subcollector region 14 and a ground pad 24 is connected to reach- through 22 through insulating layer 25.