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Semipolar {101¯1} InGaN quantum wells are grown on (001) Si substrates with an Al-free buffer and wafer-scale uniformity. The novel structure is achieved by a bottom-up nano-heteroepitaxy employing self-organized ZnO nanorods as the strain-relieving layer. This ZnO nanostructure unlocks the problems encountered by the conventional AlN-based buffer, which grows slowly and contaminates the growth chamber.

AlN nanopyramids with semipolar facets are grown by metal‐organic chemical vapor deposition (MOCVD) on the AlN substrate attained with compressed AlN powders. Surface qualities of the polycrystalline substrate are improved with an AlN buffer layer deposited by sputtering, followed by appropriate post annealing. It is found that a pulsed flow condition of ammonia (NH3) during the MOCVD growth can effectively enhance morphologic uniformity and crystallinity of the nanopyramids. The semipolar AlN nanopyramids serve as a promising template for ultraviolet emitters, considering their increased surface area and reduced polarization fields.

The effects of crosslinking polymer networks (PNs) on the molecular reorientation and electro‐optical properties of vertically aligned (VA) liquid crystal (LC) devices are investigated by applying an in‐plane switching (IPS) electric field. Through the polymerization process, crosslinking PNs are developed on the substrate surface, effectively increasing the anchoring energy and governing the LC molecular reorientation. With its stronger anchoring effect, the PNs cell shows good light transmittance and excellent vertical alignment quality, as compared to the pure LC cell. Furthermore, the alignment transformation and transmittance bounce resulting from the transient process of LC molecular reorientation are eliminated when the cell is operated at high voltages. The rising‐time (tr) and falling‐time (tf) responses of the PNs cell are significantly improved, and around 36% improvement in the optical switching response is obtained. In addition, the dynamic gray‐level tr and tf responses of the PNs cell are enhanced by around 55% and 42%, respectively, at a low driving voltage (∼12 V). This developed VA‐IPS LC/PNs cell benefits not only the LC molecular alignment but also the electro‐optical performance. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1123–1130