is there any affect of cleanroom conditions specifically humidity on the photolithography process, such as feature size, developing time ,resolution ..etc?
There is an effect. In real time, it depends on the resist and the CD you are trying to achieve. My guess is that if your CD is in few um, it should not be a huge problem. With sub um and sub 100 nm, it is surely an issue.
A good read would be Article Effect of Humidity on Photoresist Performance
For conventional diazonaphtoquinone-based resists, some water content is necessary to allow the conversion of ketene to indenecarboxylic acid, so insufficient humidity (usually below 30%) or rehydration time will cause a severe drop in sensitivity, contrast, and development rate, especially near the substrate surface.
For chemically amplified resists (CARs) it's not as straightforward and I'm not really familiar with most types of CARs, but generally, if water is not involved in the deprotection mechanism (such as resists based on trifluoromethanesulfonate photoacid generator and tert-butyloxycarbonyl protecting groups), resist sensitivity will decrease with the increase of humidity or long delay between soft bake and PEB, causing T-topping in severe cases.
As a rule of thumb, the thickness of spin-coated resist will decrease by 0.1-1% for a 1% increase in relative humidity, due to a lower solvent evaporation rate. This will be especially pronounced when short spin times or viscous photoresists are employed. You may experience inferior or even total loss of adhesion if RH > 60% due to water vapor condensation (the evaporative cooling effect may be sufficient to decrease wafer temperature below the dew point).
If your critical dimension is 5 um and strict sidewall angle, feature size and repeatability control are not really important, you should be fine as long as your relative humidity is in the range of 30-60%.
it won't affect that much, just quickly do every step and put sample into deposition chamber
I don't think, that doing things quickly is a good solution for litho, especially if RH is too low. Among other problems, hastening rehydration will effectively halt the development rate even in a few microns thick DNQ-based resists. In high RH conditions hastening litho steps is not as beneficial as one might think, because issues are mainly (but not only) related to inferior adhesion due to too high water content at the substrate-resist interface, which is defined mainly by conditions in the spin chamber.
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