Yu Q, Yu C, Wang J, Guo F, Gao S, Jiao S, Li H, Zhang X, Wang X, Gao H, Yang H, Zhao L: Gas sensing properties of self-assembled ZnO nanotube bundles. RSC Adv 2013, 3:16619–16625.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions YCL designed the experiments and drafted the manuscript. TYL carried out the sample preparations
and the material analyses. Both authors read and approved the final manuscript.”
“Background Silicon-based technology is the prime enabler for high-density integrated microelectronic circuits, optoelectronics, and photovoltaic devices with ubiquitous applications ranging from mobile devices to high-end computing and communications. As Si complementary metal-oxide-semiconductor (CMOS) circuits are
relentlessly scaled down to 16 nm or smaller dimensions, knowledge about fundamental nanoscopic #PD0332991 molecular weight randurls[1|1|,|CHEM1|]# processes in Si is becoming crucial for developing a good understanding on the limitations of nanofabrication and the development of future evolutionary directions for the technology as a whole. Many processing reactions including epitaxial growth, doping, oxidation, selleck and silicidation are affected by the native defects in Si such as vacancies, self-interstitials, and their complexes. It is believed that Si interstitials play an important role in these processes, mostly detrimental, for instance causing such effects as undesirable transient-enhanced diffusion of dopants
in p/n junctions [1, 2], metal spiking at silicide/Si interfaces , interfacial traps along the gate oxide/Si interface , and stacking faults/dislocations in the epitaxial layer [1, 5, 6]. In this paper, we report a unique effect, hitherto unreported, that is attributable to Si interstitials present within oxide layers previously generated by the selective oxidation of polycrystalline-SiGe (poly-SiGe) nanopillars leaving behind Ge quantum dots (QDs) or nanocrystallites when the preferential oxidation of Si is complete. In this novel phenomenon, these Ge QDs or nanocrystallites appear to be very sensitive to the presence of Si interstitials, almost acting as detectors for these interstitial species. The mechanism appears to be complex and long range in comparison to the typical diffusion lengths of Si interstitials within oxide layers. Methods Three different Dipeptidyl peptidase cases were considered for our experimental study. All cases consisted of heterostructures as shown in Figures 1,2,3,4. These samples were prepared using a CMOS-compatible approach by the deposition of poly-Si0.85Ge0.15 layers over buffer layers of Si3N4 or SiO2 on Si substrates using low-pressure chemical vapor deposition. In general, a multilayer deposition of Si3N4/SiO2/Si0.85Ge0.15/SiO2 was carried out sequentially on top of a Si substrate. The topmost, thin SiO2 layer is deposited as a hard mask for subsequent plasma etching for producing SiGe nanopillars.