Film formation method and apparatus for semiconductor process

Abstract

A film formation apparatus for a semiconductor process includes a process gas supply system configured to supply process gases. The process gas supply system includes a gas mixture tank configured to mix first and third process gases to form a mixture gas, a mixture gas supply line configured to supply the mixture gas from the gas mixture tank to a process field, a second process gas supply circuit having a second process gas supply line configured to supply a second process gas to the process field without passing through the gas mixture tank, and first and second switching valves disposed on the mixture gas supply line and the second process gas supply line, respectively. A control section controls the first and second switching valves to be opened and closed so as to alternately and pulse-wise supply the mixture gas and the second process gas to the process field.

1 . A film formation apparatus for a semiconductor process, comprising: 
 a process container having a process field configured to accommodate a plurality of target substrates stacked at intervals;    a support member configured to support the target substrates inside the process field;    a heater configured to heat the target substrates inside the process field;    an exhaust system configured to exhaust gas inside the process field;    a process gas supply system configured to supply process gases to the process field so as to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film;    a control section configured to control an operation of the apparatus including the process gas supply system,    wherein the process gas supply system comprises    a gas mixture tank disposed outside the process container and configured to mix the first and third process gases to form a mixture gas,    a mixture gas supply line configured to supply the mixture gas from the gas mixture tank to the process field,    first and third process gas supply circuits configured to supply the first and third process gases to the gas mixture tank, respectively,    a second process gas supply circuit having a second process gas supply line configured to supply the second process gas to the process field without passing through the gas mixture tank,    first and second switching valves disposed on the mixture gas supply line and the second process gas supply line, respectively, and    wherein the control section controls the first and second switching valves to be opened and closed so as to alternately and pulse-wise supply the mixture gas from the gas mixture tank and the second process gas from the second process gas supply circuit to the process field.    
   
   
       2 . The apparatus according to  claim 1 , wherein the control section performs control to continuously supply the first and third process gases from the first and third process gas supply circuits to the gas mixture tank, while supplying the mixture gas pulse-wise from the gas mixture tank to the process field.  
   
   
       3 . The apparatus according to  claim 1 , wherein the control section performs control to simultaneously supply the first and third process gases pulse-wise in a first phase from the first and third process gas supply circuits to the gas mixture tank, while supplying the mixture gas pulse-wise in a second phase reverse to the first phase from the gas mixture tank to the process field.  
   
   
       4 . The apparatus according to  claim 1 , wherein the mixture gas supply line and the second process gas supply line comprise first and second supply ports, respectively, each of which comprises a plurality of gas spouting holes arrayed over the target substrates in a vertical direction to form gas flows parallel with the target substrates.  
   
   
       5 . The apparatus according to  claim 1 , wherein the third process gas is supplied to the process field in an amount 1/100 or less of the first process gas.  
   
   
       6 . The apparatus according to  claim 1 , wherein the first process gas contains a silane family gas, the second process gas contains a nitriding gas or oxynitriding gas, and the third process gas contains a doping gas.  
   
   
       7 . The apparatus according to  claim 6 , wherein the process gas supply system further comprises a fourth process gas supply circuit configured to supply a fourth process gas containing a carbon hydride gas to the gas mixture tank.  
   
   
       8 . The apparatus according to  claim 6 , wherein the first process gas contains at least one gas selected from the group consisting of dichlorosilane, hexachlorodisilane, monosilane, disilane, hexamethyldisilazane, tetrachlorosilane, disilylamine, trisilylamine, and bistertialbutylaminosilane, the second process gas contains at least one gas selected from the group consisting of ammonia, nitrogen, dinitrogen oxide, and nitrogen oxide, and the third process gas contains at least one gas selected from the group consisting of BCl 3 , B 2 H 6 , BF 3,  and B(CH 3 ) 3 .  
   
   
       9 . The apparatus according to  claim 1 , further comprises an exciting mechanism configured to activate the second process gas by generating plasma.  
   
   
       10 . The apparatus according to  claim 9 , wherein the exciting mechanism comprises a plasma generation area disposed in a space communicating with the process field and between a supply port of the second process gas and the target substrates.  
   
   
       11 . A film formation apparatus for a semiconductor process, comprising: 
 a process container having a process field configured to accommodate a plurality of target substrates stacked at intervals;    a support member configured to support the target substrates inside the process field;    a heater configured to heat the target substrates inside the process field;    an exhaust system configured to exhaust gas inside the process field;    a process gas supply system configured to supply process gases to the process field so as to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film, and the third process gas is supplied to the process field in an amount smaller than that of the first process gas;    a control section configured to control an operation of the apparatus including the process gas supply system,    wherein the process gas supply system comprises    a mixture gas supply line configured to mix the first and third process gases to form a mixture gas and supply the mixture gas to the process field,    first and third process gas supply circuits having first and third process gas supply lines configured to supply the first and third process gases to the mixture gas supply line, respectively,    a second process gas supply circuit having a second process gas supply line configured to supply the second process gas to the process field without passing through the mixture gas supply line,    first, second, and third switching valves disposed on the first, second, and third process gas supply lines, respectively,    a first tank disposed on the first process gas supply line immediately before the first switching valve to temporarily store the first process gas, and    wherein the control section controls the first, second, and third switching valves to be opened and closed so as to alternately and pulse-wise supply the mixture gas from the mixture gas supply line and the second process gas from the second process gas supply circuit to the process field.    
   
   
       12 . The apparatus according to  claim 11 , wherein the control section controls the first and third switching valve to be simultaneously opened and closed.  
   
   
       13 . The apparatus according to  claim 11 , wherein the process gas supply system further comprises a second tank disposed on the third process gas supply line immediately before the third switching valve to temporarily store the third process gas  
   
   
       14 . The apparatus according to  claim 11 , wherein the mixture gas supply line and the second process gas supply line comprise first and second supply ports, respectively, each of which comprises a plurality of gas spouting holes arrayed over the target substrates in a vertical direction to form gas flows parallel with the target substrates.  
   
   
       15 . The apparatus according to  claim 11 , wherein the third process gas is supplied to the process field in an amount 1/100 or less of the first process gas.  
   
   
       16 . The apparatus according to  claim 11 , wherein the first process gas contains a silane family gas, the second process gas contains a nitriding gas or oxynitriding gas, and the third process gas contains a doping gas.  
   
   
       17 . The apparatus according to  claim 16 , wherein the process gas supply system further comprises a fourth process gas supply circuit configured to supply a fourth process gas containing a carbon hydride gas to the mixture gas supply line.  
   
   
       18 . The apparatus according to  claim 16 , wherein the first process gas contains at least one gas selected from the group consisting of dichlorosilane, hexachlorodisilane, monosilane, disilane, hexamethyldisilazane, tetrachlorosilane, disilylamine, trisilylamine, and bistertialbutylaminosilane, the second process gas contains at least one gas selected from the group consisting of ammonia, nitrogen, dinitrogen oxide, and nitrogen oxide, and the third process gas contains at least one gas selected from the group consisting of BCl 3 , B 2 H 6 , BF 3 , and B(CH 3 ) 3 .  
   
   
       19 . The apparatus according to  claim 11 , further comprises an exciting mechanism configured to activate the second process gas by generating plasma.  
   
   
       20 . The apparatus according to  claim 19 , wherein the exciting mechanism comprises a plasma generation area disposed in a space communicating with the process field and between a supply port of the second process gas and the target substrates.  
   
   
       21 . A film formation method for a semiconductor process, comprising: 
 heating a plurality of target substrates stacked at intervals within a process field in a process container; and    supplying process gases to the process field to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film,    wherein said supplying the process gases comprises    supplying the first and third process gases to a gas mixture tank disposed outside the process container to form a mixture gas,    supplying the mixture gas from the gas mixture tank to the process field, and    supplying the second process gas to the process field without passing through the gas mixture tank,    so as to alternately and pulse-wise supply the mixture gas and the second process gas to the process field.    
   
   
       22 . A film formation method for a semiconductor process, comprising: 
 heating a plurality of target substrates stacked at intervals within a process field in a process container; and    supplying process gases to the process field to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film, and the third process gas is supplied to the process field in an amount smaller than that of the first process gas,    wherein said supplying the process gases comprises    supplying the first and third process gases to a mixture gas supply line to form a mixture gas and supply the mixture gas to the process field, while temporarily storing the first process gas in a first tank disposed immediately before the mixture gas supply line, and    supplying the second process gas to the process field without passing through the mixture gas supply line,    so as to alternately and pulse-wise supply the mixture gas and the second process gas to the process field.    
   
   
       23 . A computer readable medium containing program instructions for execution on a processor, which, when executed by the processor, cause a film formation apparatus for a semiconductor process to execute 
 heating a plurality of target substrates stacked at intervals within a process field in a process container; and    supplying process gases to the process field to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film,    wherein said supplying the process gases comprises    supplying the first and third process gases to a gas mixture tank disposed outside the process container to form a mixture gas,    supplying the mixture gas from the gas mixture tank to the process field, and    supplying the second process gas to the process field without passing through the gas mixture tank,    so as to alternately and pulse-wise supply the mixture gas and the second process gas to the process field.    
   
   
       24 . A computer readable medium containing program instructions for execution on a processor, which, when executed by the processor, cause a film formation apparatus for a semiconductor process to execute 
 heating a plurality of target substrates stacked at intervals within a process field in a process container; and    supplying process gases to the process field to deposit a thin film on the target substrates, wherein the process gases include a first process gas for providing a main material of the thin film, a second process gas for reacting with the first process gas, and a third process gas for providing a sub-material of the thin film, and the third process gas is supplied to the process field in an amount smaller than that of the first process gas,    wherein said supplying the process gases comprises    supplying the first and third process gases to a mixture gas supply line to form a mixture gas and supply the mixture gas to the process field, while temporarily storing the first process gas in a first tank disposed immediately before the mixture gas supply line, and    supplying the second process gas to the process field without passing through the mixture gas supply line,    so as to alternately and pulse-wise supply the mixture gas and the second process gas to the process field.