Patent ID: 6838127
Filing Date: 2005-01-04
Classification: C23C,H01J,H01L

Abstract:
1. A method of forming an HSG-Si layer on a wafer, said method comprising: providing a process chamber having a first heater fixed in a position at a bottom thereof and a second heater located at a top thereof, the first heater having a central portion that protrudes upwardly relative to a peripheral portion thereof; placing the wafer onto the central portion of the first heater fixed in said position at the bottom of the process chamber; with the wafer disposed on the central portion of the first heater, operating the first and second heaters and exposing the wafer to heat generated by the first and second heaters and radiating within the process chamber for a period of time sufficient for the heat to remove foreign substances from the wafer; once the period of time has elapsed, injecting a source gas of HSG-Si onto the wafer supported on the central portion of the first heater while the first heater remains fixed in said position at the bottom of the process chamber, to thereby form a layer of amorphous silicon on the wafer; with the first heater still fixed in said position at the bottom of the process chamber, annealing the wafer for a predetermined period of time so that the amorphous silicon is transformed into an HSG-Si layer, and regulating the temperatures of the central and peripheral portions of the first heater independently of one another such that the temperature of the central portion of the heater on which the wafer is situated is lower than the temperature of the peripheral portion of the heater, and regulating the temperature of the second heater to maintain the temperature of the wafer constant from at least once the source gas begins to be injected into the process chamber through the end of the annealing at the lapse of said predetermined period of time.