| 摘要 |
<p>A heater and pedestal actuator (50) is provided to actuate the pedestal (34) of a deposition chamber (10) from a first position (12) wherein a wafer (30) may be placed thereon to a second position (14) adjacent to the deposition target (16). To adjust the inward travel of the heater (32) to compensate for target (16) erosion, the actuator (50) includes a worm drive apparatus (76) driven by a stepper motor (66). The worm drive (76) is pitched, and the stepper motor (66) is selected, to allow fine movement of the heater (32) on the order of less than .01 mm for each arcuate step of the stepper motor (66). A computer (400) is used to actuate the stepper motor (66), and cause additional stepper motor actuation, to increase the travel of the heater (32) toward the target (16) to compensate for target (16) erosion. Additionally, the computer (400) may vary the speed of the worm drive (76) rotation, to create different heater (32) travel speeds within the chamber (10). <IMAGE></p> |
