chemical vapor deposition and defining the active regions

... Further condensation will then produce SiNWs in the channels of alumina Furthermore, the carrier gas Ar will collide with the pore surface and the atomic Si has absorbed and exchange energy and ... growth plane is one of the (1 1) planes and the fast growth direction is along the [)2 1] axis of the SiNWs The (1 1) plane family, which is the densest packed plane with the lowest surface energy ... maintaining their orientation within the template The EDS spectra collected from the middle part of the SiNWs arrays (Fig 1c) show the presence of silicon in addition to Al and O C and Cu are...

Ngày tải lên: 16/03/2014, 15:08

... depending on whether II-VI or IIIV growth is taking place, and v and s indicate whether the species is in the vapor or solid phase The vapor phase reactants RnM and ER´n are thermally decomposed ... as the pure source becomes nearly all used, all of the condensed liquid phase evaporates and the source can no longer support its own vapor pressure The source will then be completely in the vapor ... onto the gas stream The forced flow pattern overcomes thermally induced convection and “pumps” the flow stream lines to the surface of the susceptor where they then flow laterally over the susceptor...

Ngày tải lên: 14/02/2014, 03:20

... passed through the DEZn bubbler and saturated with DEZn vapor to the reactor N2 was used as the carrier gas The substrate was cleaned in acetone, methanol, deionized water, and then chemical etched ... ZnO film and a nitrogen doped one are deposited by plasma-assisted metal-organic chemical vapor deposition (MOCVD) We have investigated their structural and optical qualities and found that the nitrogen ... water rinse The reaction temperature was 6008C and the power of the plasma source was 900 W The growth rate was mm/h The non-doped sample (sample A) was grown with O2 flow of 10 SCCM while the N-doped...

Ngày tải lên: 05/03/2014, 21:20

... by the H2 gas and Ar gas injected into the chamber for 10 The applied radio frequency power was 60 W Then, silane gas with the concentration of 2% flowed into the chamber for the coating The deposition ... for 10 and removed by annealing Most of the nanotubes are straight and have uniform dimensions along their entire lengths The average outer diameter of the nanotubes is around 170 nm and the surface ... enhance the mechanical properties of the tubes Because the PVP nanofibers were suspended in the form of alignment in the dissociated gas and had suitable packing density, the thickness of the coated...

Ngày tải lên: 22/06/2014, 00:20

... to the formula [14], the peaks at 147 and 169 cm-1 correspond to the SWCNTs with diameter of 1.59 and 1.38 nm, respectively The TEM image (Fig 3b) reveals that the product consists of single and ... represent the existence of SWCNTs are hardly shown The data show no SWCNTs are formed and there are only poorly multi-walled carbon nanotubes (MWCNTs) and organized carbon in the sample The relatively ... diameters The intensity ratio becomes lower with ID/IG = 0.32 and the TEM shows that there are only a few amorphous carbons in the SWCNTs bundle The RBM mode is observed as a strong band at 160...

Ngày tải lên: 22/06/2014, 00:20

... pretreatment of 100, 200, and 300 sccm are illustrated in Fig All the Raman spectra display two broad bands at 1,330 cm-1 (D-band) and 1580 cm-1 (G-band) The Dband is associated with the vibrations of ... that the intensity ratio of G and D bands (ID/IG) is related to the sp2 carbon cluster sizes in the graphene sheet and is nearly proportional to the defect density The ID/IG ratio is 0.96, 0.92 and ... elastic energy and surface energy of the carbon layer caused the radius of curvature of the Ni catalyst particle to become small The rising gradient of the surface energy, then enhanced the surface...

Ngày tải lên: 22/06/2014, 01:20

... uniform and the density of the dendrites was dependent on the amount of In and the distance of the silicon from the In The In2O3 NCs grown at TG = 1000 °C on silicon exhibited clear peaks in the ... powder Then the boat was loaded into the quartz tube reactor and positioned directly above the thermocouple used to measure the heater temperature at the centre of tube After loading the boat ... = 400 °C and d 20 lm isolated flower-like structure Nanoscale Res Lett (2009) 4:491–497 expand as the growth proceeds thereby leading to the coalescence of the NCs and the formation of the wreathlike...

Ngày tải lên: 22/06/2014, 01:20

... covered the substrate surface tightly, and then the top layer provided the seeds of the rods If the OGC were high enough as the precursor, the tungsten oxide nanorods would keep yielding If not, the ... well They were vertical to the substrate The diameter of the rod was 400 nm averagely The number of rods per unit area (Fig 1b) was almost the same as the number of the total particles on the ... surface of the sample (Fig 1a) Therefore, it could be assumed that the particles on the top layer in sample (a) could be the base of the tungsten oxide rods shown in Fig 1b The particles on the bottom...

Ngày tải lên: 22/06/2014, 18:20

... at the bottom left and the target adenine is at the top of each model The sidechains of RTA are shown in blue (A) Model has the tetraloop bound in the active site of RTA with G4 stacked upon the ... R213D in the vicinity of residue 213 The backbone and sidechains of the R213D substitution are shown as stereo images in thick ball and stick and the position of the Arg213 side-chain of the wild-type ... 213, 234 and 235 [9] Of theses residues, only Arg213 is in the vicinity of the active site of RTA In order to establish the role of arginyl residues around the active site of RTA in the binding...

Ngày tải lên: 19/02/2014, 12:20

... unit area of the gate insulator, and q is max the unit charge The estimated S and Ns of the TFTs are 13 4.70 V/decade and 2:58 Â 10 /cm , respectively The fieldeffect mobility (FE ) and threshold ... before reaching the substrate For the ZnO film growth, the flow rates of DEZn and oxygen were 6.7 and 3:3 Â 105 mmol/min, respectively The reactor pressure was maintained at 50 Torr and the growth temperature ... respectively The DEZn source was maintained at a temperature of  C and Ar was used as its carrier gas The DEZn and O2 were separately introduced into the reactor and the mixing of these two sources...

Ngày tải lên: 05/03/2014, 21:20

... quartz plate The other RF electrode was placed cm above The ®lament was placed between these two RF electrodes The distance between the substrate and the ®lament could be adjusted The as-grown ... image of the nanowires with carbon deposition at $1300°C and the higher magni®cation image of a part of the sample in the upper image feather-like carbon sheets sprouting from the surface of the nanowires ... not be formed very well on the surface of nanowires because of both the volume change of the nanowires and breaking of the carbon network sheathed on the nanowires When the substrate temperature...

Ngày tải lên: 16/03/2014, 15:04

... also facilitate the pyrolysis and deposition of silane on iron and growth of the SiNWs because of their carbothermal reduction The growth process proposed here which is different from the conventional ... among the Si simple index surfaces In a word, with the assistance of the CNTs and the catalysis of Fe particles, preference of taking the least lattice mismatch between Si and Fe leads to the growth ... at the end of the carbon nanotubes with high density These SiNWs tended to ÔstickÕ to each other The diameter of the SiNWs is about 50–70 nm, which is well consistent with the diameter of the...

Ngày tải lên: 16/03/2014, 15:06

... Au–Si island-catalyzed rapid thermal chemical vapor deposition (RTCVD) The initial nucleation of the NWs from the Au–Si islands is examined while varying island sizes Also, we investigate the variation ... diagram [8] The surface shape of the islands is smooth and circular even though the edge of the islands are irregular in Figs 1(a) and (b), indicating that the islands were formed from the liquid ... film, the average diameter of the islands was 8 nm and all islands were smaller than 20 nm (Fig 1(a)) while for 2.0 nm Au film, the average diameter was 13 nm and the fraction of the islands...

Ngày tải lên: 16/03/2014, 15:15

... band to band electron–hole recombination in the SiNWs obtained by a CVD method The passivation of the SiNW surfaces is essential to reduce the deep trap density and allow the observation of the ... explain the energy shift and the change in the spectrum shape compared to the bulk silicon (free Fig Normalized intensity of the PL measurements of the as-grown (red dash–dot curve) and passivated ... affect the gap energy and not the electron/hole effective masses Thus, the computation of the ehp emission spectrum depends on electronic temperature and ehp density Fig shows the comparison of the...

Ngày tải lên: 16/03/2014, 15:19

... treated for and 20 s, the amorphous carbon domains are eliminated, and the tubes become smoother and cleaner as shown in Fig.1(b) and (c) After 60 and 90 s, as seen in Fig.1(e) and (f), the carbon ... destroy the outside walls Using the Brunauer–Emmett–Teller (BET) method, the adsorption isotherms of N2 on the MWCNTs were measured for all the samples Fig Adsorption and desorption isotherms ... be due to the defects and amorphous carbons, which decrease the gas adsorption capability Applying the BET method to the data in Fig yields the monolayer adsorption capacity (Vm) and the specific...

Ngày tải lên: 20/03/2014, 13:06

... the bandgap, Ec, Ev, is the conduction and valence band, respectively, and DEc, DEv is the conduction band and valence band discontinuities, respectively The values of the energies shown in the ... DEv,1, DEv,2 and DEv,3 represent the band energy offsets of the light, heavy and split-off band at the valence band, respectively The energy splitting of the conduction band is given by the following ... L is the QW width and E1e and E1hh are the energy values of the first energy state in the conduction and valence bands mB , mW , mB and mW are the e e hh hh effective mass of the electron and heavy...

Ngày tải lên: 22/06/2014, 22:20

... image under α if and only if they have the same active partition, and one can be obtained from the other by reorienting parts of the active partition The number of regions in the inverse image ... shows the active mapping for the example of Figures and The active paths for the two fibers associated with 12 are shown In these two fibers, for regions associated with 127 or 128, the active ... Suppose a is active, and consider the case where p = a Since n is the greatest letter, and is not at an end of either one, p and p have the same active letters The letter i1 on the left...

Ngày tải lên: 07/08/2014, 08:22

... uplift the roofs, blowoff the windows and doors of the houses The gust-wind in the very strong typhoons can fully damage the houses or structural parts of the houses Therefore, understanding the ... number of the typhoons hitting Vietnam The coastal areas most suffering from the typhoons are from the South of the Middle-part to the North of Vietnam 2.3 Typhoon-affected regions The inland regions ... stability and stiffness of the single wall The RC bond beam (the width equals to the thickness of the wall, the thickness is from 150 to 200 mm) should be placed at the level above the windows and...

Ngày tải lên: 01/04/2013, 22:47

... the activity Given the 3D structure of the HtA active site, and the interactions between side chains, we propose that D40, H42, R95 and F126 also form part of it As in other ribotoxins, the active ... from the idealized covalent geometry, and most of the backbone torsion angles for amino acid residues lie within the allowed regions in the Ramachandran plot The statistics characterizing the ... the structure of the remaining part is the same in both proteins, including a short segment (N56, C57 and D58) forming a turn of 310 helix (D75, C76 and D77 in a-sarcin) The active site The active...

Ngày tải lên: 18/02/2014, 08:20

... conned to the substrate binding cleft (the 170 loop) in the active site region and the S1 pocket, whereas the intramolecular connections, for instance between the TF-binding region and the active ... in the vicinity of the S1 pocket [11,34], in the rst part of activation loop 3, and in the area of the TF-interactive helix and the 170 loop [8,35], areas that are stabilized by TF [9,25,26] The ... substrate subsites located in the vicinity of the active site and sensed by the peptidyl substrate are inuenced, in contrast to the remote exosites, e.g in the vicinity of the activation pocket, that...

Ngày tải lên: 18/02/2014, 08:20