Permeable polymer membrane for dessication of gas

A method for etching a semiconductor wafer, a semiconductor device, or an intermediate thereof, which comprises:

• using a gas which has been desiccated by preparing a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR25## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane;
• and
• bringing said gas into contact with one side of said membrane, and either bringing a dry purge gas into contact with the other side of said membrane or reducing the pressure on said other side of said membrane thereby removing water from said water-containing gas.

A method of oxide coating in the production of a semiconductor wafer, a semiconductor device, or an intermediate thereof, which comprises:

• forming said oxide coating by the use of an ordinary gas and/or a corrosive gas which has been desiccated by preparing a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR26## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane;
• and
• bringing said ordinary and/or corrosive gas into contact with one side of said membrane, and either bringing a dry purge gas into contact with the other side of said membrane or reducing the pressure on said other side of said membrane thereby removing water from said ordinary gas and/or corrosive gas.

A method for cleaning the surface of a semiconductor wafer, a CVD device, and an impurity diffusing furnace in the production of the semiconductor wafer, a semiconductor device, or an intermediate thereof, which comprises:

• passing a raw material gas through an entire system and thereafter effecting said cleaning by the use of a gas which has been desiccated by preparing a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR27## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane;
• and
• bringing said gas into contact with one side of said membrane, and either bringing a dry purge gas into contact with the other side of said membrane or reducing the pressure on said other side of said membrane thereby removing water from said gas.

A method for diffusing impurities in the production of a semiconductor wafer, a compound semiconductor wafer, a semiconductor device, a compound semiconductor device, and/or an intermediate thereof, which comprises:

• diffusing said impurities on said semiconductor wafer of said compound semiconductor wafer by the use of a doping gas which has been desiccated by preparing a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR28## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane;
• and
• bringing said doping gas into contact with one side of said membrane, and either bringing a dry purge gas into contact with the other side of said membrane or reducing the pressure on said other side of said membrane thereby removing water from said doping gas.

A method for forming a coating on a substrate placed under a vacuum or atmospheric pressure, which comprises:

• introducing a raw material gas for the formation of said coating and/or a carrier gas into the system enclosing said vacuum or atmospheric pressure therein, wherein said raw material gas and/or carrier gas has been desiccated by preparing a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR29## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane;
• and
• bringing said raw material and/or carrier gas into contact with one side of said membrane, and either bringing a dry purge gas into contact with the other side of said membrane or reducing the pressure on said other side of said membrane thereby removing water from said raw material gas and/or carrier gas.

A method for producing a permeable polymer membrane having a water absorption ratio, W, and an ion-exchange capacity, Q, represented by the following formula:

• 1.20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane, which comprises:
• forming a membrane of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR30## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, and heating the membrane at a temperature in the range of 60.degree. C. to 250.degree. C.

An apparatus for forming a thin-film, comprising:

• a film-forming chamber capable of maintaining the interior thereof under a vacuum or atmospheric pressure,
• a gas inlet for introducing a gas from a gas supply source into said film-forming chamber,
• vacuumizing means capable of evacuating said film-forming chamber of a gas, and
• water separating means interposed between said gas inlet and said gas supply source, wherein said water separating means comprises a casing having inserted therein a multiplicity of hollow fibers of a permeable polymer membrane formed of a fluorine type copolymer containing a repeating unit represented by the general formula:
• ##STR32## wherein m is 0 or 1 and n is an integer of the value of 2 to 5, said permeable polymer membrane being thermally treated at a temperature in the range of 60.degree. C. to 250.degree. C. and having a water absorption ratio, W, and an ion-exchange capacity, Q, which are represented by the following formula:
• 1. 20Q-1.964<log W<1.20Q-1.742
• wherein W is (W.sub.2 -W.sub.1)/W.sub.1, W.sub.1 is a dry weight, W.sub.2 is an equilibrium weight as immersed in pure water at 25.degree. C., and Q is an ion-exchange capacity in meq/g of H form dry resin in the form of a membrane, with the opposite ends of said hollow fibers fixed in place with resin in such a manner that different gases are passable outside and inside said hollow fibers.