Fabrication and experimental characterization of a sol–gel derived nanostructured n-ZnO/p-Si heterojunction diode

Abstract

In this paper, fabrication and characterization of a sol-gel derived n-ZnO nanoparticle/p-Si heterojunction diode has been presented. A strong diffraction peak (002) obtained from XRD spectra of sol-gel derived ZnO thin film indicates that the growth of hexagonal wurtzite ZnO nanoparticles are preferably along the c-axis. The surface morphological features extracted from AFM and SEM images predict the uniform growth of ZnO nanoparticles over the p-Si substrate. The optical properties of ZnO nanoparticles have been measured in the spectral range of 300-1000 nm using ellipsometer and photoluminescence spectroscopy. The optical transmittance of ZnO nanoparticles has been observed between 81 and 92.66 % in visible region and the optical band gap has been found out to be 3.24 eV. Finally, metallic contacts were deposited on top of ZnO layer and bottom of Si layer to perform electrical characterization of nanostructured n-ZnO/p-Si heterojunction diodes. Electrical parameters including reverse saturation current, ideality factor, barrier height, rectification ratio have been calculated to explore the potential of the device for futuristic nanoelectronic and optoelectronic device applications.

Effect of annealing temperature on structural, electrical, and UV sensingcharacteristics of n-ZnO/p-Si heterojunction photodiodes

“…• C annealing are also associated with the formation of the interfacial layer, which degrades the stoichiometric structure of the ZnO/Si interface [23]. However, the obtained n and ϕ b values are almost as good as or even better than those of n-ZnO/p-Si heterojunction devices reported in previous studies [28,[35][36][37]. ( ε : ∼3.9) or Zn-containing silicate ( ε : ∼6.5) layers are lower than ZnO ( ε : ∼8.5).…”

Solution-route low-temperature fabrication of thin-film p-n junctions

“…The higher transmittance characteristics in the visible region for ZnO-sys2, however, may be due to the smoother surface as determined by the AFM images (figure S2) and c-axis oriented crystallites as revealed in the XRD results (figure 3). At higher energy region, a moderate absorption is observed, while other reports show a sharp absorption edge [15,18]. High UV transmission yield is expected due to thinner films.…”

“…Several research groups developed sol-gel-based p-n heterojunction photodiodes at high temperatures [11][12][13][14][15]. By growing p-n junctions at elevated temperatures using successive spin coatings, they demonstrated prominent electrical performance such as a large rectification ratio, a significant quantum efficiency, and ideality factors close to ideal diodes.…”

“…One approach to lowering the heterojunction fabrication temperature is based on reaction chemistry of the precursors. The stock solution reported previously [11,[13][14][15][16][17] was slightly modified to promote the elimination of organics from the film at low temperature. On the other hand, the UV-assisted TA method has exhibited the effective formation of metal-oxide semiconductor and dielectrics from sol-gel precursors [23][24][25].…”

Impact of deposition temperature on crystalline quality, oxygen vacancy, defect modulations and hetero-interfacial properties of RF sputtered deposited Ga2O3 thin films on Si substrate

“…For the heterojunction devices, the ideality factors are calculated and summarized in table 1. The values of ideality factor are greater than unity due to the presence of defect states in the β-Ga 2 O 3 thin films, interface states and nonlinear inhomogeneities of barrierheights at metal-semiconductor junctions [47] Barrier height for all the heterojunctions are also calculated by using the equations given in [48]. The barrier height is found to be lowest for 600 • C deposited Ga 2 O 3 thin film heterojunctions (0.623 eV).…”