Impact of Phase Transformation in WO₃ Thin Films at Higher Temperature and its Compelling Interfacial Role in Cu/WO₃/p–Si Structured Schottky Barrier Diodes

Abstract

Inter-connected network grains of tungsten trioxide (WO3) thin films were deposited on glass using a jet nebulizer spray pyrolysis (JNSP) technique by varying the substrate temperature at 350, 400, 450 and 500 °C. Phase transformation (monoclinic to orthorhombic) was observed during the film growth through X-ray diffraction (XRD) analysis. Field emission scanning electron microscope (FE-SEM) images revealed a better grain growth with smooth surface for 400 °C. The WO3 film deposited at 400 °C exhibits minimum band gap and maximum optical conductivity of 3.2 eV and 5.8 × 1014 (Ω.cm)−1. From the current-voltage (I–V) characteristics, the mean electrical conductivity is found to increase gradually and the activation energy reduced at higher substrate temperature. Cu/WO3/p–Si structured Schottky barrier diodes (SBDs) have been fabricated with different substrate temperature and it was tested under variable device temperatures ranging from 30 to 170 °C. The experimental results of all SBDs indicated a linear reduction in the ideality factor (n) with a small increment in effective barrier height (ΦB) with increase in device temperature, which is due to lateral inhomogeneity’s at the interface. Moreover, the minimum n value of 2.89 and their corresponding ΦB of 0.71 eV were recorded for device temperature at 170 °C. Compared with other SBDs, the device fabricated at 400 °C demonstrated a better thermal stability and device performance.

Slow Magnetic Relaxation in {[CoCxAPy)] 2.15 H2O}n MOF Built from Ladder-Structured 2D Layers with Dimeric SMM Rungs

“…This is attributed to the tetramethyldisiloxane spacer in Cx ligand, which is very flexible and unable to develop significant intermolecular interactions, constituting the amorphous part of the structure. This may be a cause for which the diffractogram recorded at room temperature ( Figure S6a ) is slightly different from that simulated after single crystal X-ray diffraction experiments at 200 K. At room temperature, which is above T g , the flexible segments begins to relax, causing the interplanary distance to increase [ 32 , 33 ]. Another cause of the non-conformity of the experimental diffractograms with the theoretical ones found in the case of both compounds ( Figure S6a,b ) could be the adoption by the tetramethyldisiloxane segment of different conformations during the crystallization process that leads to various polymorph modifications.…”

Excellent physicochemical and sensing characteristics of a RexOy based pH sensor at low post-deposition annealing temperature

“…p-Type silicon (Si), selected as the substrate due to its low work function and good adhesion to oxide thin film, 24 was cleaned by immersing in hydrofluoric acid (HF) : DI water = 1 : 100 solution to remove the native SiO 2 from the surface. The Si substrate was treated in a drying oven at 100 °C for 10 minutes to remove the surface water.…”

Oncurrent-voltage and capacitance-voltage characteristics of metal-semiconductor contacts

“…The bias dependent I − V curves in Figure 20 are plotted using Eq. (19). However, the basis of pinch-off model plays an important role in carrier transport.…”

“…Figure19. The effective barrier height at a pinched-off eΦ b,ef f is slightly smaller than that behind a spatially homogeneous high barrier-height region, eΦ hom = eΦ b0 , but is much larger than the barrier height behind a spatially low barrier-height region, eΦ b,patch .…”

“…The current transport mechanism across MS contact depends on the ideality of the fabricated MS junction, and it is determined from the electrical measurements with sample temperature. To fully understand the electrical properties and behavior of a SBD , the experimental electrical measurements must be taken at different sample temperatures and the characteristic diode parameters must be evaluated from these measurements [15][16][17][18][19][20][21].…”