Particle-removing method for a semiconductor device manufacturing apparatus
View Patent ↗In a semiconductor device manufacturing apparatus that processing a substrate by applying a voltage to a gas to create a plasma, positively charged particles are trapped or guided at the instant that the cathode voltage is stopped, by an electrode to which is imparted a negative voltage, so as to prevent particles reaching the substrate.
1. A particle-removing method for a semiconductor device manufacturing apparatus that comprises an etching processing chamber, a pair of processing electrodes formed by an upper electrode and a lower electrode, which are installed within said processing chamber, and a susceptor that holds a substrate to be processed onto the top of said lower electrode, a processing gas being introduced into said etching processing chamber, and a prescribed voltage being applied to said processing electrodes, so as to generate a plasma of said gas, thereby processing said substrate on said susceptor, a particle-removing electrode being provided for the purpose of removal of particles in said processing chamber, and a purge gas being introduced into said processing chamber after completion of etching of said substrate, wherein a negative voltage is applied to said particle-removing electrode during a period from a time before stopping applying said prescribed voltage to said processing electrode to a time after starting introducing said purge gas into said processing chamber, so as to remove charged particles inside said processing chamber.
2. The particle-removing method according to claim 1 , wherein said charged particles are positively charged particles.
3. The particle-removing method according to claim 1 , wherein said negative voltage is applied to said particle-removing electrode, so as to trap said charged particles to said particle-removing electrode.
4. The particle-removing method according to claim 1 , wherein said particle-removing electrode is a cover that covers said substrate.
5. The particle-removing method according to claim 1 , wherein said particle-removing electrode is a gas exhaust port provided at the bottom of said processing chamber.
6. The particle-removing method according to claim 1 , wherein said particle-removing electrode is an attachment-prevention shield between said processing electrodes and the side wall of said processing chamber.
7. The particle-removing method according to claim 1 , wherein said negative voltage applied to said particle-removing electrode has an absolute value that is greater than a self-bias voltage of said lower electrode.