Method for Early Determination of Leakages in Polysilicon Emitter Transistor Fabrication Using an Electron Beam
Original Publication Date: 1986-Jan-01
Included in the Prior Art Database: 2005-Mar-08
A non-destructive method is proposed for early detection of leakages in polysilicon emitter transistors. Electron Beam Induced Current (EBIC) testing would be done at an earlier stage than after metallization, as is normally the case. This would permit completion of fabrication of chips with known leakage limited yield, and make it possible to more easily identify clustering of defects. Conventionally, to determine leakages in transistors, chains of devices are formed using metal wiring. Electrical testing is next done to determine defect types and densities. This takes place several steps after transistor fabrication is completed and is usually limited to test sites, as opposed to the wafer areas that will actually be used for product chips. EBIC testing can be done on the chains to localize defects.