System and method to supply chemical during semiconductor device fabrication

Abstract

Disclosed are a system and method for supplying chemical during a semiconductor device fabrication process. The system includes a tank to store the chemical, a dispensing unit to hold the chemical, a refill line connected between the tank and the dispensing unit to supply the chemical from the tank to the chemical liquid dispensing unit, and a dispensing line connected between the chemical dispensing unit and a semiconductor substrate to supply the chemical from the chemical dispensing unit to the semiconductor substrate.

1 . A method of supplying chemical onto a semiconductor substrate, comprising:
 storing the chemical in a tank;   filling a dispensing unit with chemical from the tank through a refill line;   dispensing chemical onto the semiconductor substrate through a dispensing line; and   refilling the dispensing line with chemical from the tank.   
     
     
         2 . The method of  claim 1 , wherein the refill line and the dispensing line share a common line, and wherein the commonly shared line is adapted to refill the dispensing unit with the chemical from the tank, and also adapted to dispense the chemical from the dispensing unit. 
     
     
         3 . The method of  claim 1 , wherein the refill line, dispensing line, and the commonly shared line are connected to a three-way valve, and the three-way valve is adapted to open and close the refill line, dispensing line, and the commonly shared line. 
     
     
         4 . The method of  claim 1 , wherein the chemical has a high viscosity of more than about 500 cP. 
     
     
         5 . The method of  claim 4 , wherein the chemical is a photoresist, a non-photosensitive polyimide, or a photosensitive polyimide. 
     
     
         6 . The method of  claim 1 , further comprising a vent line connected between the dispensing unit and a 2-way valve. 
     
     
         7 . The method of  claim 1 , wherein the dispensing unit comprises a pump and a cylinder.