Plasma ignition validation in a plasma-assisted wafer process background

1 . An apparatus for semiconductor processing, the apparatus comprising:

a reactor chamber configured to process a wafer;

a plasma generator provided to the reactor chamber to generate a plasma in the reactor chamber;

a plasma control board operably connected to the plasma generator and provided with a power control to control plasma power in the reactor chamber; and

a process controller operably connected to the plasma control board and configured to set plasma parameters for the plasma in the reactor chamber,

wherein the plasma control board comprises a plasma power measurement sensor and is constructed and programmed to determine a count of both a number of plasma pulses having the plasma power enter into a plasma power valid range when the plasma power goes up through a plasma power low threshold and a number of plasma pulses having the plasma power enter into the plasma power valid range when the plasma power goes down through a plasma power high threshold.

2 . The apparatus according to claim 1 , wherein the plasma control board is further configured to transmit the count to the process controller.

3 . The apparatus according to claim 1 , wherein the process controller is configured to set off an alarm in response to the count being below a predetermined value range and in response to the count being above the predetermined value range.

4 . The apparatus according to claim 1 , wherein the process controller is configured to adjust the plasma parameters.

5 . A semiconductor processing method in an apparatus comprising a reactor chamber configured to process a wafer, a plasma generator configured to generate a plasma in the reactor chamber, a plasma control board comprising a plasma power measurement sensor, and the plasma control board operably connected to the plasma generator and provided with a power control to control plasma power in the reactor chamber, and a process controller operably connected to the plasma control board and configured to set plasma parameters for the plasma in the reactor chamber, the method comprising:

setting, with the process controller, the plasma parameters from recipe or operator input;

sending the plasma parameters from the process controller to the plasma control board;

sensing and determining, with the plasma control board, a count of a number of good pulses in the plasma power;

receiving, by the process controller, the count of the number of good pulses from the plasma control board; and

determining, based on the count of the number of good pulses, whether a number of good ignitions is within a predetermined acceptable range or not,

wherein the count of the number of good pulses includes both a number of plasma pulses having the plasma power enter into a plasma power valid range when the plasma power goes up through a plasma power low threshold and a number of plasma pulses having the plasma power enter into the plasma power valid range when the plasma power goes down through a plasma power high threshold.

6 . The method according to claim 5 , further comprising:

determining that the number of good ignitions is not within the predetermined acceptable range; and

setting an alarm in response to the determining that the number of good ignitions is not within the predetermined acceptable range.

7 . The method according to claim 5 , further comprising adjusting the plasma parameters.

8 . A non-transitory, computer-readable, and tangible medium having stored thereon a set of instructions that, when executed by a processor of a computer system, cause the computer system to:

set plasma parameters from recipe or operator input;

send the plasma parameters to a plasma control board;

cause the plasma control board to sense and determine a count of a number of good pulses in plasma power during processing of a wafer in a reactor chamber;

receive the count of the number of good pulses from the plasma control board; and

determine, based on the count of the number of good pulses, whether a number of good ignitions is within a predetermined acceptable range or not,

wherein the count of the number of good pulses includes both a number of plasma pulses whose plasma power enters into a plasma power valid range when the plasma power goes up through a plasma power low threshold and a number of plasma pulses whose plasma power enters into a plasma power valid range when the plasma power goes down through a plasma power high threshold.

9 . The apparatus according to claim 1 , wherein the process controller is configured to display an indication that the count is outside a predetermined acceptable range.

10 . The apparatus according to claim 1 , wherein the process controller is configured to terminate processing of the wafer in response to the count being below a predetermined value range and in response to the count being above the predetermined value range.

11 . The method according to claim 5 , further comprising displaying an indication that the number of good ignitions is not within the predetermined acceptable range.

12 . The method according to claim 5 , further comprising terminating processing of the wafer in the reactor chamber in response to determining that the number of good ignitions is not within the predetermined acceptable range.

13 . The non-transitory, computer-readable, and tangible medium according to claim 8 , wherein the instructions, when executed by the processor of the computer system, cause the computer system to display an indication that the number of good ignitions is not within the predetermined acceptable range.

14 . The non-transitory, computer-readable, and tangible medium according to claim 8 , wherein the instructions, when executed by the processor of the computer system, cause the computer system to terminate processing of the wafer in the reactor chamber in response to determining that the number of good ignitions is not within the predetermined acceptable range.