Patent 7537968 was granted and assigned to SanDisk on May, 2009 by the United States Patent and Trademark Office.
A method for annealing a diode formed of a silicon-germanium alloy that minimizes leakage current is disclosed. The method includes the steps of forming semiconductor pillars of an alloy of silicon and germanium; heating the pillars at a first temperature for at least 30 minutes, and then heating the pillars at a second temperature higher than the first temperature of the alloy for up to 120 seconds. The invention further includes a monolithic three dimensional memory array of a plurality of p-i-n diodes, the p-i-n diodes being formed of a silicon-germanium alloy that have been subjected to a two-stage heating process.