Hall parameters were measured at 300 K. Electron concentration is 4.6 × 1019 cm−3 with a sheet resistance of 58 Ω/ . Electron mobility at 300 K is 69.7 cm2/VS. Figure 7 Current–voltage curve of Si-doped GaN nanowall network grown with a N/Ga ratio of 400. Therefore, this nanowall network structure is promising in fields where a large surface/volume ratio is needed, for instance, gas sensors based on surface change after exposing to a particular gas. Compared with separated nanostructures, such as nanowires and nanoparticles, its continuous characteristic along the lateral direction makes it much easier to fabricate to various

electronic devices. Moreover, Si substrate is helpful for integrated sensors through the combination with silicon micromachining GSK2118436 purchase as well as conventional Si electronics. Conclusions Continuous GaN nanowall network was grown on Si (111) substrate by MBE under N2-rich condition. GaN nanowalls overlap and interlace with one another, together with large numbers of holes, forming a continuous GaN nanonetwork. XRD and PL results show that the GaN nanowall network is of high quality. By adjusting the N/Ga ratio, the nanowall width can be varied from 30 to 200 nm. This kind of nanostructure can be fabricated to electronic nanodevices as Nirogacestat in vitro easily as

GaN film. In addition, growth of GaN on silicon makes it compatible with the most mature silicon-based semiconductor technology. Acknowledgment The authors are grateful to F. R. Hu for his great help in operating the MBE system and F. Iguchi as well as T. Miyazaki for their help in the XRD and TEM measurements. The authors would also like to thank Y. Etofibrate Kanamori, T. Wu, and T. Sasaki for the discussion. This work was supported by the research projects, Grant-in-Aid for Scientific Research (A 24246019) and μSIC. A. Zhong appreciates the China Scholarship Vactosertib in vivo Council (CSC) for the financial support. References 1. Wierer JJ, Krames MR, Epler JE, Gardner NF, Craford MG: InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal structures.

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