Vacuum prcessing apparatus and vacuum processing method of sample

Abstract

A vacuum processing apparatus includes a vacuum container which can be depressurized, a sample holder inside of the vacuum container for mounting a sample to be processed, wherein films laid over a surface of the sample are etched with plasma generated in a space above the sample holder. The apparatus further includes a gas supply channel for feeding a heat conducting gas between a sample mounting surface and the backside of the sample, and a pressure control unit for changing stepwise the pressure of the gas supply channel between the sample mounting surface and the backside of the sample in accordance with the progress of the processing of the films of the sample by the etching.

1 . A vacuum processing apparatus comprising a vacuum container inside of which can be depressurized, a sample holder located inside of the vacuum container to mount thereon a sample to be processed, for etching films laid over the sample surface with plasma generated in a space above the sample holder inside of the vacuum container, wherein the apparatus further comprising:
 a gas supply channel for feeding a heat conducting gas between a sample mounting surface and the backside of the sample; and   a pressure control unit for changing stepwise the pressure of the gas supply channel between the sample mounting surface and the backside of the sample in accordance with the progress of the processing of the films of the sample by the etching.   
   
   
       2 . The vacuum processing apparatus according to  claim 1 , wherein the pressure control unit reducing the pressure stepwise when the processing reaches the interface between the films or vicinity of the interface. 
   
   
       3 . The vacuum processing apparatus according to  claim 1  or  2 , wherein the pressure control unit further comprising a valve which is placed on a gas exhaust channel, communicated with the gas supply channel and serving to discharge the heat conducting gas from the gas supply channel, and whose opening degree can be controlled stepwise. 
   
   
       4 . The vacuum processing apparatus according to  claim 1  or  2 , wherein the pressure control unit comprising a pair of a first gas exhaust channel and a second gas exhaust channel, wherein
 the first gas exhaust channel, having an orifice and a valve whose opening degree can be controlled stepwise, communicated with the gas supply channel and serving to discharge the heat conducting gas from the gas supply channel, and   the second gas exhaust channel, not having an orifice, communicated with the gas supply channel and serving to discharge the heat conducting gas from the gas supply channel.   
   
   
       5 . A vacuum processing apparatus comprising a vacuum container the inside of which can be depressurized, a sample holder which is located inside of the vacuum container and constitutes a substrate electrode on which a sample to be processed is mounted, used for etching films mounted over the surface of the sample with plasma generated in a space above the sample holder inside of the vacuum container; wherein the apparatus further comprising:
 a power supply connected to the substrate electrode for supplying electrical power during the etching;   a gas supply channel for feeding a heat conducting gas between a sample mounting surface of the sample holder and the backside of the sample;   a pressure control unit for changing stepwise the pressure of the gas supply channel between the sample mounting surface and the backside of the sample in accordance with the progress of the processing of the films of the sample; and   a power control unit for changing stepwise the output of the power source in accordance with the progress of the processing of the films of the sample by the etching.   
   
   
       6 . The vacuum processing apparatus according to  claim 5 , wherein
 the pressure control unit is capable of reducing the pressure stepwise when the processing reaches the interface between the films or the vicinity of the interface, and   the power control unit is capable of heightening the power stepwise when the processing reaches the interface between the films or the vicinity of the interface.