Method to control etch profile by rf pulsing

A system for performing a plasma etch process, comprising:

• a chamber configured to receive a substrate for processing;
• a high frequency generator that generates a high frequency (HF) RF signal, said HF RF signal being pulsed in a three-state cycle including a first state, a second state, and a third state;
• wherein the first state is configured at a first power level;
• wherein the second state is configured at a second power level less than the first power level;
• wherein the third state is configured at a third power level less than the second power level;
• wherein the second power level is in the range of about 0 W to 3500 W,
• wherein the HF RF signal is applied to an electrode of the chamber for performing the plasma etch process.

A non-transitory computer readable medium having program instructions embodied thereon that, when executed by at least one processor, cause said at least one processor to execute a method for performing a plasma etch process, said method comprising:

• receiving a substrate into a chamber;
• generating a high frequency (HF) RF signal, said HF RF signal being pulsed in a three-state cycle including a first state, a second state, and a third state;
• wherein the first state is configured at a first power level;
• wherein the second state is configured at a second power level less than the first power level;
• wherein the third state is configured at a third power level less than the second power level;
• wherein the second power level of the HF RF signal is in the range of about 0 to 3500 W,
• wherein the HF RF signal is applied to an electrode of the chamber for performing the plasma etch process.