Influence of the pellicle on final photomask flatness

Wistrom, Richard; Hayden, Dennis; Racette, Kenneth C.; Barrett, Monica; Watts, Andrew

doi:10.1117/12.681775

Cited by 4 publications

(2 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Components such as pellicle mounting techniques, pellicle frame height, frame material and adhesive all play an important role in finished photomask flatness. [1][2][3][4][5] In particular, recent studies have shown that adhesive flexibility affect final photomask flatness significantly. 6 This has motivated pellicle suppliers to optimize adhesive properties and to evaluate new adhesives.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of easily removable pellicle adhesive

et al. 2010

Self Cite

View full text Add to dashboard Cite

With the advancement of technology, the need to produce flatter photomasks is critical to meet strict mask manufacturing requirements. Components such as pellicle mounting techniques, pellicle frame height, frame material and adhesive all play an important role in finished photomask flatness.1-5 In particular, recent studies have shown that adhesive flexibility affect final photomask flatness significantly.6 This has motivated pellicle suppliers to optimize adhesive properties in addition to evaluate new adhesives.The paper describes the joint evaluations between IBM, Toppan and MLI, performed to determine the effect of a new MLI adhesive on the distortion of photomasks. Due to the nature of this adhesive, minimal mounting force is required. As a result of utilizing extreme low mounting pressure, benefits such as decreased flatness distortion and ease of adhesive removal are observed. The goal of this paper is to evaluate this new adhesive offering and understand the various impacts it has on pelliclized photomasks for advanced technologies.

show abstract

Section: Introductionmentioning

confidence: 99%

Evaluation of easily removable pellicle adhesive

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…During certain conditions crystals formation of haze form on reticle surfaces, the sulfate ion (SO 4 2-) left on the mask surface after SPM (scanning probe microscopes) step is known the most important source cause for the formation of haze defects. And ammonium sulfate has been known to be mostly responsible for haze defects formation on the mask surface, recent investigation reveals that other chemicals such as hydrocarbons, Na, F, Mg, K, Cl or Al are also cause haze defects.…”

mentioning

confidence: 99%

A N 2 /CDA reticle purging approach with enhanced efficiency

Tseng²,

Lee³

et al. 2008

SPIE Proceedings

View full text Add to dashboard Cite

Haze is a kind of contamination on the surface of mask which observed in the wafer production clean room only on reticles exposed with 193nm or 248nm wavelength process. In the lithography process, the wafer damage has been occurred due to the growth of haze in semiconductor manufacturing, haze defect for 193 nm lithography needs to be improved, and the improvement involves not only the selection and use of appropriate materials but also the minimization of running cost and reticle purging time as well as the prevention of haze generation. During certain conditions crystals formation of haze form on reticle surfaces, the sulfate ion (SO 4 2-) left on the mask surface after SPM (scanning probe microscopes) step is known the most important source cause for the formation of haze defects. And ammonium sulfate has been known to be mostly responsible for haze defects formation on the mask surface, recent investigation reveals that other chemicals such as hydrocarbons, Na, F, Mg, K, Cl or Al are also cause haze defects. A major problem in the integrated circuit (IC) industry is that the manufacturing process may experience malfunction due to haze contamination on the mask once the reticle has been exposed to ArF radiation. It is therefore crucial to detect and control the haze defects to keep the manufacturing process in smooth operation and to improve throughput.Analyses have been provided an approach with enhance reticle purging efficiency method for investigating the required purging flow of clean, dry gas to prevent the ingestion of external contaminants into the reticle. The generally-accepted solution is to purge the RSP (Reticle SMIF Pod) with nitrogen to continuously flow and diffuse slowly through the pellicle. However, purging the pellicle space can be time-consuming as it requires considerable care to avoid causing rupture in the pellicle film due to pressure difference across the pellicle film and reticle-purging is to supply N2/CDA into RSP (Reticle SMIF Pod) to facilitate slow diffusion of clean air in the space between the reticle and pellicle. In performing the purging, the frame is placed in Reticle SMIF Pod and high purity nitrogen is supplied into the Reticle SMIF Pod until the oxygen content drops below the required level; exposure can then begin. This is obviously a time-consuming process, and that is why a more efficient way is needed to reduce the purification time.In this study, we investigate the purging parameters theoretically by using natural convection with the purpose of Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/21/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspxavoiding rupturing the pellicle and expediting the overall purging process as shown in fig.1. Accordingly, a parametric analysis of important geometric variables including the size and number of purging holes is performed. Our study then process to identify the optimized parameters (number of holes, position of holes, purging flow rate) by using computational fluid dynamic (CFD) simulation....

show abstract