Plasma processing apparatus
A plasma processing apparatus for controlling a length of a first output duration of a microwave power and a length of a second output duration to obtain a desired etching rate distribution of a wafer, in which one cycle of pulse modulation includes a first output duration of a microwave output and a second output duration having a finite value smaller than the first output, and an OFF duration. An etching rate distribution is a concave distribution for the first output and a convex distribution for the second output, and a control device controls a pulse generator such that when the etching rate distribution is the concave distribution, a length of the first output duration is longer than a length of the second output duration, and when the etching rate distribution is the convex distribution, the length of the first output duration is shorter than the length of the second output duration.
1. A plasma processing apparatus comprising:
a processing chamber configured to allow a sample to be subjected to plasma processing;
a radio-frequency power supply configured to supply a radio-frequency power for generating plasma;
a sample stage configured to allow the sample to be placed; and
a control device configured to control a length of a first duration having an amplitude of a finite value or a length of a second duration having an amplitude of a finite value such that an etching rate distribution in plasma processing is a desired etching rate distribution when the radio-frequency power is modulated by a pulse having the first duration, the second duration, and a third duration having an amplitude of zero, wherein
the radio-frequency power in the first duration is a power in which the etching rate distribution is a first etching rate distribution, and
the radio-frequency power in the second duration is a power in which the etching rate distribution is a second etching rate distribution.
2. The plasma processing apparatus according to claim 1 , wherein
the length of the first duration and the length of the second duration are independently controlled by the control device.
3. The plasma processing apparatus according to claim 1 , wherein
when the first etching rate distribution is the desired etching rate distribution, the length of the first duration or the length of the second duration is controlled by the control device such that the length of the first duration is longer than the length of the second duration.
4. The plasma processing apparatus according to claim 2 , wherein
when the first etching rate distribution is the desired etching rate distribution, the length of the first duration or the length of the second duration is controlled by the control device such that the length of the first duration is longer than the length of the second duration.
5. The plasma processing apparatus according to claim 3 , wherein
when the second etching rate distribution is the desired etching rate distribution, the length of the first duration or the length of the second duration is controlled by the control device such that the length of the first duration is shorter than the length of the second duration.
6. The plasma processing apparatus according to claim 4 , wherein
when the second etching rate distribution is the desired etching rate distribution, the length of the first duration or the length of the second duration is controlled by the control device such that the length of the first duration is shorter than the length of the second duration.
7. The plasma processing apparatus according to claim 1 , wherein
the amplitude in the first duration is larger than the amplitude in the second duration.
8. The plasma processing apparatus according to claim 1 , wherein
the third duration is a duration between the first duration and the second duration.
9. The plasma processing apparatus according to claim 7 , wherein
the third duration is a duration between the first duration and the second duration.
10. The plasma processing apparatus according to claim 5 , wherein
the third duration is a duration between the first duration and the second duration.
11. The plasma processing apparatus according to claim 1 , wherein
the first etching rate distribution is a concave distribution, and
the second etching rate distribution is a convex distribution.
12. The plasma processing apparatus according to claim 3 , wherein
the first etching rate distribution is a concave distribution, and
the second etching rate distribution is a convex distribution.