ABSTRACT
Can isotropic wet chemical etching be controlled with a spatial resolution at the nanometer scale, especially, for the repetitive microfabrication of hierarchical 3D µ-nanostructures on the continuously curved surface of functional materials? We present an innovative wet chemical etching method called "electrochemical buckling microfabrication": first, a constant contact force is applied to generate a hierarchical 3D µ-nanostructure on a mold electrode surface through a buckling effect; then, the etchant is electrogenerated on-site and confined close to the mold electrode surface; finally, the buckled hierarchical 3D µ-nanostructures are transferred onto the surface of a Ga x In1-x P coated GaAs wafer through WCE. The concave microlens, with a Fresnel structure, has an enhanced photoluminescence at 630 nm. Comparing with energy beam direct writing techniques and nanoimprint lithography, this method provides an electrochemical microfabrication pathway for the semiconductor industry, with low cost and high throughput.
ABSTRACT
OBJECTIVE: To discuss the indications, surgery methods and effects of the BAHA implantation by analyzing the patients' medical records of bone-anchored hearing aids(BAHA). METHODS: Retrospective analyzed the records of 16 patients of BAHA implantation, including nine males and seven females. Their average age was 31 years old (8-53ys). Nine of them were congenital ear malformation, two were chronic suppurative otitis media, two were otosclerosis and three were unilateral severe sensorineural deafness. We evaluated their pure tone audiometry (PTA), speech audiometry and temporal CT before the surgery, and evaluated the aided PTA in soundfield and speech audiometry in sound field. RESULTS: These patients received BAHA implantation and installed the speech processor their months later. The average preoperative PTA measurements (PTA at 0.5, 1, 2, 4 kHz) was (63.2 ± 19.0) dB HL and postoperative aided PTA in sound field was (35.5 ± 10.9)dB HL. The average improvement in Hearing In Noise Test (HINT) was 37.0% ± 31.7%. The average improvement in Mandarin Speech Test was 76.0% ± 19.7%. After 4-16 months' follow-up, no significant complications were recorded. CONCLUSION: BAHA is a safe and effective bone implantable hearing device.
