Dry Dispensing Process, Process Parameters On The Stripping Rate Impact

Photoresist removal technology plays a very important role in the microelectronics industry, accounting for 30% of IC manufacturing cost.It brings a direct impact on product yield and manufacturing costs of devices and circuits. Photoresist removal process uses plasma for photoresist ashing. Photoresist ashing process has significant advantages over wet photoresist removal process. It has a higher etching rate and less environmental pollution, it is easier to be precisely controlled and has been widely used in the modern semiconductor industry.The defects related to photoresist residue cause yield loss in photoresist ashing process and sometimes the frequency of such defects formation is very high. So it is urgent to solve this problem. In addition, modern fab's monthly shipments is very large, without the well control of such defects it is difficult to improve the product yield.It will also affect the fab production capacity improvement and degrade the company image.In this paper, the impact of the parameters of photoresist ashing process on the impact of ashing rate, such as temperature, RF power, gas flow and reaction pressure is studied. It is revealled that the temperature of the ashing process can significantly influence the ashing rate, while RF power and oxygen gas flow aslo have effective influence. A little effect is observed for reaction pressure.Therefore, in daily industrial production, once the defect of photoresist residue is observed we can check the temperature first and then the RF power and gas flow. A final check can be done for reaction pressure. Thus,we can quickly solve engineering problems.