Sodium hypochlorite as a developer for heavy ion tracks in polyimide

The developing and etching of heavy ion tracks in polyimide with sodium hypochlorite have been studied to gain control over the parameters that affect the etch result. The shape of the resulting pores is a function of both alkalinity and hypochlorite content of the solution. Sodium hypochlorite decomposes during etching, and the rate constant has been determined as a function of the alkalinity at 62 degreesC. Polished cross-sections have been examined to determine the pore shape, and this method has shown to he a straightforward way to characterise the pores. Decreasing the alkalinity gives more cylindrical pores, but increases the decomposition rate of the hypochlorite solution and decreases the etch rate. (C) 2001 Elsevier Science B.V. All rights reserved.