Surface profile control of the autocloned photonic crystal by ion-beam-sputter deposition with radio-frequency-bias etching

摘要

[[abstract]]Growth of the autocloned Ta2O5/SiO2 multilayer photonic crystal with a lateral sawtooth period was simulated. Ion-beam sputter (IBS) was applied to deposit the films and radio-frequency-bias (RF-bias) etching was applied simultaneously with the IBS on the Ta2O5 film. Both simulation and experiment showed that the quality of the autocloning can be controlled by the RF-bias power; there is an intermediate power range within which the drop of peak-to-valley height variation of the sawtooth profile can be reduced significantly such that a high degree of autocloning can be achieved. Analysis showed that simultaneous deposition and etching at the proper RF-bias power on the Ta2O5 film has the capability to compensate the flattening effect of the SiO2 deposition such that the sawtooth surface profile can be maintained.