>> Mirror Haze Measurement of Scanner for Color Filter Plant
We introduced the information about our service for one of color filter manufacturer to identify the haze on its mirror in the Other Information of e-News Vol.017 Aug. 2009.
In this issue, we will propose a quantified data for further reference.
>> Preface
Preface
The scanner used for color filter is different from that used for very narrow width in semiconductor manufacturing and then it is not so accurate.
However, the operation of optics behavior is the same regardless of color filter or semiconductor manufacturing. The basic feature is to enclose the high energy light source inside a close space and this is the reason why haze happens.
Some analysis and data will be shown here for further reference.
>> Method
Method
The whole procedures could be categorized into two sections：one is environment quantification and another one is sampling on the mirror surface.
We focused only on inorganic and MEA in this sampling/analysis work. As for environment analysis, the well-known impinger was applied and a clean wipe for extraction of substances on the mirror was used.
>> Analysis Result
Analysis Result
Please find the following table for the analysis result.
>> Discussions
Discussions
Referring to the above table, the deposition of SO42-on the mirror surface owns highest level although the environment air concentration is low. It could be expected that sulfur compounds are easy to stick on the surface of mirror or still some other sulfur compounds exist which cannot be captured by impinger. And this should be reviewed from the overall process layout.
And if the time factor could be considered in the above table, the data of μg/cm2 hr could be defined and it will be more helpful for benchmarking.
>> Conclusions
Conclusions
Based on the same sampling method, we could set the relationship between accumulation rate and environment concentration and such kind of database would be helpful for benchmarking and control of haze problem.