EFFECT OF OXIDE PRECIPITATE SIZE ON SLIP GENERATION IN LARGE-DIAMETEREPITAXIAL WAFERS

The effect of oxide precipitate size on slip generation was investigat ed in Czochralski (CZ), p/p-, p/p+ and p/p++ epitaxial wafers during d evice manufacturing. In high-temperature processes where maximum tempe rature reaches 1100 degrees C, the mechanical strength of epitaxial wa fers was far superior to that of CZ wafers. In contrast, the mechanica l strength of all wafers was sufficiently maintained in low-temperatur e processes where maximum temperature reaches 1050 degrees C. The slip dislocation generation can be explained according to the size of oxid e precipitate formed in each wafer; precipitates larger than approxima tely 200 nm can generate slip dislocations.