| 主权项 |
1. A plasma reactor comprising:
a cylindrical microwave cavity overlying a workpiece processing chamber, and first and second coupling apertures in a sidewall of said cylindrical microwave cavity spaced apart by an angle; a microwave source having a microwave frequency and comprising a microwave controller having respective microwave outputs coupled to respective ones of said first and second coupling apertures, each of said microwave controllers comprising:
(a) a source of first and second digital modulation signals having a frequency corresponding to a slow rotation frequency;(b) a source of a first digital carrier signal having an intermediate frequency;(c) a multiplier stage comprising a pair of multipliers each having a pair of inputs, said multiplier stage coupled to receive, respectively, (a) said first digital modulation signal, said second digital modulation signal and said first digital carrier signal, respectively, said multiplier stage having respective outputs, in1 and in2;(d) a digital-to-analog converter coupled to receive said respective outputs in1 and in2 and having analog outputs corresponding to said outputs in1 and in2; and an up-converter having inputs coupled to said analog outputs, said up-converter comprising said microwave outputs. |
