System Design for Maximizing Uniformity in Selective Epitaxial Refill Processes
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Feb-01
A method has been developed for achieving uniform levels of refill over a wafer during the selective epitaxial refill process. This is accomplished by eliminating local turbulent gas flow across the surface of the wafer which had contributed to the non-uniformity of the wafer. When wafers 1 (Fig. 1) were examined, it was noted that higher refill levels were obtained within the cross-hatched area 2. This area, which might amount to 15% of the wafer's surface, was at the top edge of the wafer as it sat in the susceptor tool and was the portion of the wafer first contacted by the gas flow 3 across its surface. In the refill process, the wafer 1 (Fig. 2) sits in a recess 4 in the susceptor tool 5 with the gas 3 flowing downward across the wafer.