用于集成电路制造的光刻胶剥离和或光掩模清洁的工艺顺序

A method and system for cleaning and/or stripping photo  resist from photomasks used in integrated circuit manufac  turing comprising a process and means of introducing a  mixture of sulfuric acid and ozone (or a mixture of sulfuric  acid and hydrogen peroxide) to the Surface of a photomask  while applying megaSonic energy. The invention also com  prises method and system comprising a process and means  of introducing oZonated deionized water and/or a low tem  perature dilute aqueous solution (dAPM) to the surface of  photomasks while applying megaSonic energy. The process  and apparatus also remove post plasma ashed residues and  other contaminants from photomask Surfaces.

process that includes a photolithographic processing step.  A photolithographic process step uses photomasks (or  reticles) in combination with a light Source to optically  project a circuit image onto the Surface of a silicon wafer or  Substrate that has a light-sensitive layer, such as photoresist, applied to its Surface. A photomask is a transparent ceramic  Substrate that is coated with a metallic layer forming a  pattern for an electronic circuit. During the manufacture of  ICs, a pellicle is typically used to seal the photomask from  particulate contamination, thereby isolating and protecting  the photomask surface from dust or other particles from the  focal plane of the photomask pattern.

In order to produce functioning ICs at a high yield rate,  the photomask and pellicle need to be free of contamination.  Contamination of the photomask can occur both during the  manufacture of the photomask itself, and during use of the  photomask in the IC manufacturing process, specifically  during processing and/or handling of the photomask. One  type of contamination is organic/molecular contamination of  the photomask Surface. Organic/molecular contamination,  Such as chemical stains or residues, on the Surface of the  photomask reduces and degrades the transmittance property and/or characteristic of the photomask, ultimately impacting  the qual.

Cs during the photolithography process is particulate con  tamination. Particulate contamination may include any Small  particles, such as dust particles, that may be on the photo  mask or caught between the photomask and the pellicle. Particulate contamination may cause the photolithographic  pattern transmitted on the wafer to change, distort, alter, etc.  from its intended design, ultimately impacting the quality of  the semiconductor device manufactured.

Fig1

Still another aspect of photomask manufacturing process  which is known to affect the quality of the circuit patterns projected during photolithography is the stripping of pho  toreist from the photomask surface. Similar to the manufac  ture of the IC devices, during the manufacture of the  photomask, photoresist is applied to Surface of the photo  mask and light and/or ultraviolet radiation is applied to the  photomask Surface in a desired circuit pattern. Once the  exposure is completed, the photoresist is removed from the  surface of the photomask, thereby revealing the circuit pattern. Proper removal of photoresist is required so as to  ensure that the circuit pattern is not changed, distorted,  altered, etc. from its intended design.