Plasma etching method

摘要

A plasma etching method by using a plasma etching apparatus having a depressurizable processing chamber; a lower electrode for mounting thereon a substrate to be processed in the processing chamber; an upper electrode facing the lower electrode in the processing chamber with a plasma generation region formed therebetween; a radio frequency power supply unit for applying a radio frequency power between the upper electrode and the lower electrode to thereby form a radio frequency electric field in the plasma generation region, the method comprising: supplying a first gas including etchant gas to an upper gas inlet to introduce the first gas through the upper electrode into the plasma generation region; and feeding a second gas including dilution gas to a side gas inlet to introduce the second gas through a sidewall of the processing chamber into the plasma generation region.

主权项

1. A plasma etching method performed in a plasma etching apparatus having a depressurizable processing chamber, a lower electrode for mounting thereon a substrate to be processed in the processing chamber, an upper electrode facing the lower electrode in the processing chamber with a plasma generation region formed therebetween, a radio frequency power supply unit for applying a radio frequency power between the upper electrode and the lower electrode to thereby form a radio frequency electric field in the plasma generation region, the method comprising:
supplying a second gas to a first gas inlet to introduce the second gas through a first region containing a central portion of the upper electrode into the plasma generation region; feeding a first gas to a second gas inlet to introduce the first gas through a second region of the upper electrode provided at an outside of the first region along its radial direction into the plasma generation region; and supplying the second gas to a third gas inlet to introduce the second gas through a third region of the upper electrode provided at an outside of the second region along its radial direction into the plasma generation region, wherein the first gas consists of an etchant gas and the second gas consists of a dilution gas, wherein the second gas is introduced through the first gas inlet and the third gas inlet so that the first gas introduced through the second gas inlet is maintained between a central portion and a peripheral portion of the plasma generation region, and wherein the dilution gas is at least one species of gas selected from the group consisting of Ar, CO, and O2.