Experimental Study On Reactive Shock Wave Etching Of Monocrystalline Silicon

The theoretical and experimental research shows that the shock wave is produced when the sound wave with limited amplitude propagates and short pulse in the liquid arrives at surface of materials. The shock wave has the characteristics of high energy and instantaneous great pressure.Reactive shockwave etching, which is based on the focused of pulse ultrasound technology, is presented. Due to the non-linear propagation effects, the high-energy transient pressure wave is introduced by a shockwave generator producing the focused of pulse ultrasound (1MHz or so). Combined with wet etching process, the material in focused zone can be etched quickly by physical and chemical process.Details are as follows:1. According to the structure characteristic of mono crystalline silicon, reactive shock wave etching of mono crystalline silicon is researched. Sonochemistry and dynamics of etching are analyzed.2. On the basis of system principle, the experiment system is developed. The generator, the power and the etching rate are tested. The focus area of pulsed ultrasound is measured. The regional size of the focus area is analyzed. The impact of shock wave frequency on the biggest pressure and focal plane is analyzed in the paper.3. The masking layer and etching solution are chose for experiments. In comparison with ultrasound bath and magnetic stirring methods, experiments show that shock wave can reduce surface roughness and increase the etch rate by increasing the mass transport. Furthermore, the influence of etchant concentrations, temperature, power of shock wave and the principle of reactive shock wave etching of mono crystalline silicon are also analyzed, which is the foundation for the further theoretical and experimental research.