Spatial atomic layer deposition chamber with plasma pulsing to prevent charge damage
Apparatus and methods of processing a substrate in a plasma enhanced spatial atomic layer deposition chamber. A substrate is moved through one or more plasma processing regions and one or more non-plasma processing regions while the plasma power is pulsed to prevent a voltage differential on the substrate from exceeding a breakdown voltage of the substrate or device being formed on the substrate.
1. A processing method comprising:
positioning a substrate within a batch processing chamber comprising a plurality of process regions separated by gas curtains, the substrate having a breakdown voltage;
moving the substrate from a first processing region without a plasma to a second processing region with a plasma; and
pulsing a power of the plasma in the second processing region to prevent a voltage differential on the substrate from exceeding the breakdown voltage,
wherein pulsing the power comprises supplying power to the plasma for an ON time and not supplying power for an OFF time, the OFF time being sufficient to allow the voltage differential on the substrate to discharge to less than or equal to 5% of the breakdown voltage and the plasma is not extinguished during the OFF time.
2. The method of claim 1 , wherein the processing regions have a size smaller than a size of the substrate.
3. The method of claim 1 , wherein the substrate is moved at a speed sufficient so that any given point on the substrate is exposed to the second processing region for a time in the range of 100 millisecond to 500 millisecond.
4. The method of claim 2 , wherein the time is 200 milliseconds.
5. The method of claim 1 , wherein the ON:OFF time is in the range of 4:6 to about 6:4.
6. The method of claim 1 , wherein the ON:OFF time is 1:1.
7. The method of claim 1 , wherein the ON time is in the range of 1 μsec to about 50 μsec.
8. The method of claim 1 , wherein the OFF time is in the range of 1 μsec to about 50 μsec.
9. The method of claim 1 , wherein during the ON time, the substrate accumulates a voltage differential less than or equal to 95% of the breakdown voltage.
10. The method of claim 9 , wherein the substrate accumulates a voltage differential less than or equal to 80% of the breakdown voltage.
11. The method of claim 1 , wherein the OFF time is sufficient to allow the voltage differential on the substrate to discharge to less than or equal to 1% of the breakdown voltage.
12. The method of claim 1 , wherein each of the processing regions is pie-shaped and the substrate is rotated about a central axis of a susceptor assembly.
13. A processing method comprising:
positioning a substrate on a susceptor assembly within a batch processing chamber comprising a plurality of pie-shaped processing regions arranged in circular shape, each of the pie-shaped processing region separated form an adjacent processing region by a gas curtain, the substrate having a breakdown voltage, the plurality of pie-shaped processing regions including a first processing region with a plasma and a second processing region with a plasma, the second processing region sized so that the entire substrate does not fit within the second processing region at one time;
rotating the substrate on the susceptor assembly around an axis of the susceptor assembly to move the substrate from the first processing region to the second processing region; and
pulsing a power of the plasma in the second processing region comprising supplying power to the plasma for an ON time and not providing power to the processing region for an OFF time, the ON time and OFF time configured to prevent a voltage differential on the substrate from exceeding the breakdown voltage and the plasma is not extinguished during the OFF time.
14. The method of claim 13 , wherein the substrate is moved at a speed sufficient so that any given point on the substrate is exposed to the second processing region for a time in the range of 100 μsecond to 500 μsecond.
15. The method of claim 13 , wherein the ON:OFF time is 1:1.
16. The method of claim 13 , wherein during the ON time, the substrate accumulates a voltage differential less than or equal to 95% of the breakdown voltage and during the OFF time, the voltage differential on the substrate to discharge to less than or equal to 1% of the breakdown voltage.
17. A processing chamber comprising:
a susceptor assembly to support a plurality of substrates and rotate the plurality of substrate about a central axis of the susceptor assembly, the susceptor assembly having a top surface with a plurality of recesses sized to hold the substrates;
a gas distribution assembly having a front surface spaced from the top surface of the susceptor assembly to form a gap, the gas distribution assembly including a plurality of gas ports and vacuum ports to provide a plurality of gas flows into the gap and a plurality of vacuum flows to remove gases from the gap, the plurality of gas ports and vacuum ports arranged to form a plurality of process regions, each process region separated from adjacent process regions by a gas curtain, at least one of the processing regions being a plasma processing region and at least one of the processing regions being a non-plasma processing region; and
a controller coupled to the susceptor assembly and the gas distribution assembly, the controller having a first configuration to rotate the susceptor assembly about the central axis, a second configuration to provide a flow of gas into the non-plasma processing region, a third configuration to provide a flow of gas into the plasma processing region, a fourth configuration to provide power to the plasma processing region to ignite a plasma and a fifth configuration to pulse the power to the plasma processing region to generate an ON time and an OFF time for the plasma processing region, the OFF time being sufficient to allow the voltage differential on the substrate to discharge to less than or equal to 5% of the breakdown voltage and the plasma is not extinguished during the OFF time.