Resist developers and rinses

It has also been reported that water in the developing solvents may cause scumming with negative resists, particularly on silica surfaces. It tends to concentrate at the silica surface of wafers during the develop process. This is a location with high local resin concentration in the developing solvent, and, as a nonsolvent, it can cause precipitation in the form of a thin resin scum under some conditions. 

Positive resist developers, comprised entirely of solutions of alkaline metal or amine salts and bases, dissolve away the exposed areas of the resist, leaving 

Davidson, Tech. Papers, Reg. Tech. Conf. Soc. Plast. Eng., Mid Hudson Sec., p. 141 (Oct. 

Salts thus formed are dissolved in the developing solution, resulting in the decrease of the pH of the solution as the developing process proceeds. The absorption of carbon dioxide from the ambient air by the developer also consumes the free alkalinity in the developer, an occurrence that is not generally problematic in strongly buffered developers, but does affect dilute nonbuffered developer solutions appreciably.  

Endermann and W. Neugebauer, Light sensitive omicron quinone diazides and the photomechanical preparation of printing plates therewith, U.S. Patent No. 3,148,983 (1964). W.S. DeForest, Photoresist Materials and Processes, p. 157, McGraw Hill, New York (1975). ibid. 

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