Substrate liquid-processing method, substrate liquid-processing apparatus, and storage medium

Abstract

First, hydrofluoric acid is supplied to the circumferential edge of a substrate W while the substrate W provided with a polysilicon film is rotated, to remove a natural oxide film provided along the circumferential edge of the substrate W by etching so as to expose the polysilicon film. Next, hydrofluoric-nitric acid is supplied to the circumferential edge of the substrate W while the substrate W from which the polysilicon film is exposed is rotated, to remove the polysilicon film by etching. Such operation is performed by controlling a rotational driving unit 20 , a hydrofluoric acid supplying unit 54 , and a hydrofluoric-nitric acid supplying unit 52 by a control unit 50 of a substrate liquid-processing apparatus 1.

1 . A substrate liquid-processing apparatus comprising:
 a holding unit configured to hold a substrate;   a rotational driving unit configured to rotate the holding unit;   a hydrofluoric acid supplying unit configured to supply hydrofluoric acid to the circumferential edge of the substrate held by the holding unit;   a hydrofluoric-nitric acid supplying unit configured to supply hydrofluoric-nitric acid to the circumferential edge of the substrate held by the holding unit; and   a control unit configured to control the rotational driving unit, the hydrofluoric acid supplying unit, and the hydrofluoric-nitric acid supplying unit, the control unit performing control such that the hydrofluoric acid is supplied to the circumferential edge of the substrate by the hydrofluoric acid supplying unit while the substrate provided with a polysilicon film is rotated, to remove a natural oxide film provided along the circumferential edge of the substrate by etching so as to expose the polysilicon film, and then the hydrofluoric-nitric acid is supplied to the circumferential edge of the substrate by the hydrofluoric-nitric acid supplying unit while the substrate from which the polysilicon film is exposed is rotated, to remove the polysilicon film by etching.   
     
     
         2 . The substrate liquid-processing apparatus according to  claim 1 , wherein the control unit performs the control of the rotational driving unit so as to rotate the substrate, when the hydrofluoric-nitric acid is supplied to the circumferential edge of the substrate, at a rotation speed lower than that when the hydrofluoric acid is supplied to the circumferential edge of the substrate. 
     
     
         3 . The substrate liquid-processing apparatus according to  claim 1 , wherein the hydrofluoric-nitric acid supplying unit supplies the hydrofluoric-nitric acid to the position outward in the diameter direction of the substrate from the position in which the hydrofluoric acid is supplied to the substrate when the hydrofluoric acid is supplied to the circumferential edge of the substrate by the hydrofluoric acid supplying unit. 
     
     
         4 . The substrate liquid-processing apparatus according to  claim 3 , wherein the hydrofluoric-nitric acid supplying unit is positioned outward in the diameter direction of the substrate held by the holding unit from the hydrofluoric acid supplying unit. 
     
     
         5 . A substrate liquid-processing method which uses the substrate liquid-processing apparatus according to  claim 1 , comprising:
 supplying hydrofluoric acid to the circumferential edge of a substrate while the substrate provided with a polysilicon film is rotated, to remove a natural oxide film provided along the circumferential edge of the substrate by etching so as to expose the polysilicon film; and   supplying hydrofluoric-nitric acid to the circumferential edge of the substrate while the substrate from which the polysilicon film is exposed is rotated, to remove the polysilicon film by etching.   
     
     
         6 . The substrate liquid-processing method according to  claim 5 , wherein when the hydrofluoric-nitric acid is supplied to the circumferential edge of the substrate, the substrate is rotated at a rotation speed lower than that when the hydrofluoric acid is supplied to the circumferential edge of the substrate. 
     
     
         7 . The substrate liquid-processing method according to  claim 5 , wherein when the hydrofluoric-nitric acid is supplied to the circumferential edge of the substrate, the hydrofluoric-nitric acid is supplied to the position outward in the diameter direction of the substrate from the position in which the hydrofluoric acid is supplied to the substrate when the hydrofluoric acid is supplied to the circumferential edge of the substrate. 
     
     
         8 . A storage medium which stores a program capable of being executed by a control computer of the substrate liquid-processing apparatus according to  claim 1 , in which the program is executed so that the control computer controls the substrate liquid-processing apparatus to execute the substrate liquid-processing method,
 the substrate liquid-processing method including:   supplying hydrofluoric acid to the circumferential edge of a substrate while the substrate provided with a polysilicon film is rotated, to remove a natural oxide film provided along the circumferential edge of the substrate by etching so as to expose the polysilicon film; and   supplying hydrofluoric-nitric acid to the circumferential edge of the substrate while the substrate from which the polysilicon film is exposed is rotated, to remove the polysilicon film by etching.