scholarly journals Impact of Substrate Temperature on Structural, Electric and Optical Characteristics of CuO Thin Films Grown by JNS Pyrolysis Technique

Silicon ◽  
2022 ◽  
Author(s):  
N. Jhansi ◽  
D. Balasubramanian ◽  
Jih-Hsing Chang ◽  
K. Mohanraj ◽  
R. Marnadu ◽  
...  
2021 ◽  
Author(s):  
Jhansi N ◽  
Balasubramanian D ◽  
Jih-Hsing Chang ◽  
Mohanraj Kumar ◽  
Marnadu Raj ◽  
...  

Abstract JNS pyrolysis route has been successfully employed to grow CuO thin films at various substrate temperature, ranging from 300 to 600˚C. The XRD analyses revealed the monoclinic phased polycrystalline growth of the samples and exhibited the strong influence of the substrate temperature (ST) on the crystallite sizes. Optical transmission and bandgap studies also showed that sample bandgaps clearly rely upon the growth temperatures. The SEM micrographs displayed the agglomerated growth of particles having golf ball-like structures. The occurrence of Cu and O in the samples were confirmed through EDS analyses. The studies on DC electrical conductivities also shows strong dependency on the ST. A p-CuO/n-Si diode was fabricated at the ST of 600˚C and the diode parameters like barrier height ( ϕb ) and ideality factor (n) were determined under light and dark conditions.


2012 ◽  
Vol 502 ◽  
pp. 111-115
Author(s):  
J.H. Gu ◽  
Z.Y. Zhong ◽  
X. He ◽  
J. Hou ◽  
C.Y. Yang

Zinc oxide (ZnO) thin films were deposited by RF magnetron sputtering on glass substrates employing a sintered ceramic target and pure argon gas. The influence of substrate temperature on microstructure and optical characteristics of the deposited films were investigated by X-ray diffractometer (XRD) and spectrophotometer. The results demonstrate that all the ZnO films have preferred orientation along (002) direction. The substrate temperature significantly affects the crystalline quality and optical characteristics of the ZnO thin films. With the increase of substrate temperature, the mean grain size, lattice spacing and optical bandgap of the films increase, the dislocation density and micro strain decrease, and the average transmitance in the wavelength range of the visible spectrum also increases.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aziz Ahmed ◽  
Seungwoo Han

AbstractN-type bismuth telluride (Bi2Te3) thin films were prepared on an aluminum nitride (AlN)-coated stainless steel foil substrate to obtain optimal thermoelectric performance. The thermal co-evaporation method was adopted so that we could vary the thin film composition, enabling us to investigate the relationship between the film composition, microstructure, crystal preferred orientation and thermoelectric properties. The influence of the substrate temperature was also investigated by synthesizing two sets of thin film samples; in one set the substrate was kept at room temperature (RT) while in the other set the substrate was maintained at a high temperature, of 300 °C, during deposition. The samples deposited at RT were amorphous in the as-deposited state and therefore were annealed at 280 °C to promote crystallization and phase development. The electrical resistivity and Seebeck coefficient were measured and the results were interpreted. Both the transport properties and crystal structure were observed to be strongly affected by non-stoichiometry and the choice of substrate temperature. We observed columnar microstructures with hexagonal grains and a multi-oriented crystal structure for the thin films deposited at high substrate temperatures, whereas highly (00 l) textured thin films with columns consisting of in-plane layers were fabricated from the stoichiometric annealed thin film samples originally synthesized at RT. Special emphasis was placed on examining the nature of tellurium (Te) atom based structural defects and their influence on thin film properties. We report maximum power factor (PF) of 1.35 mW/m K2 for near-stoichiometric film deposited at high substrate temperature, which was the highest among all studied cases.


1998 ◽  
Vol 545 ◽  
Author(s):  
J. C. Caylor ◽  
A. M. Stacy ◽  
T. Sands ◽  
R. Gronsky

AbstractBulk skutterudite phases based on the CoAs3 structure have yielded compositions with a high thermoelectric figure-of-merit (“ZT”) through the use of doping and substitutional alloying. It is postulated that further enhancements in ZT may be attained in artificially structured skutterudites by engineering the microstructure to enhance carrier mobility while suppressing the phonon component of the thermal conductivity. In this work the growth and properties of singlephase CoSb3 and IrSb3 skutterudite thin films are reported. The films are synthesized by pulsed laser deposition (PLD) where the crystallinity can be controlled by the deposition temperature. Powder X-ray diffraction (PXRD), Transmission electron microscopy (TEM) and Rutherford- Back Scattering (RBS) were used to probe phase, structure, morphology and stoichiometry of the films as functions of growth parameters and substrate type. A substrate temperature of 250°C was found to be optimal for the deposition of the skutterudites from stoichiometric targets. Above this temperature the film is depleted of antimony due to its high vapor pressure eventually reaching a composition where the skutterudite structure is no longer stable. However, when films are grown from antimony-rich targets the substrate temperature can be increased to at least 350°C while maintaining the skutterudite phase. In addition, adhesion properties of the films are explored in terms of the growth mode and substrate interaction. Finally, preliminary room temperature electrical and thermal measurements are reported.


2008 ◽  
Vol 1111 ◽  
Author(s):  
Celine Lecerf ◽  
Philippe Marie ◽  
Cedric Frilay ◽  
Julien Cardin ◽  
Xavier Portier

AbstractPhotoluminescence activity was observed for neodymium-doped gallium oxide thin films prepared by radiofrequency magnetron co-sputtering. Structural and optical properties of as-grown and annealed films were studied and photoluminescence activity was especially investigated. The most intense lines were associated to the 4F3/2  4I9/2 and 4F3/2  4I11/2 electronic transitions of Nd3+. The effects of deposition and treatment parameters such as the substrate temperature, the post anneal treatment or the neodymium content in the films were particularly examined with the aim to reach the best luminescence efficiency.


2018 ◽  
Vol 5 (2) ◽  
pp. 171179 ◽  
Author(s):  
Bramaramba Gnapareddy ◽  
Sreekantha Reddy Dugasani ◽  
Junyoung Son ◽  
Sung Ha Park

DNA is considered as a useful building bio-material, and it serves as an efficient template to align functionalized nanomaterials. Riboflavin (RF)-doped synthetic double-crossover DNA (DX-DNA) lattices and natural salmon DNA (SDNA) thin films were constructed using substrate-assisted growth and drop-casting methods, respectively, and their topological, chemical and electro-optical characteristics were evaluated. The critical doping concentrations of RF ([RF] C , approx. 5 mM) at given concentrations of DX-DNA and SDNA were obtained by observing the phase transition (from crystalline to amorphous structures) of DX-DNA and precipitation of SDNA in solution above [RF] C . [RF] C are verified by analysing the atomic force microscopy images for DX-DNA and current, absorbance and photoluminescence (PL) for SDNA. We study the physical characteristics of RF-embedded SDNA thin films, using the Fourier transform infrared spectrum to understand the interaction between the RF and DNA molecules, current to evaluate the conductance, absorption to understand the RF binding to the DNA and PL to analyse the energy transfer between the RF and DNA. The current and UV absorption band of SDNA thin films decrease up to [RF] C followed by an increase above [RF] C . By contrast, the PL intensity illustrates the reverse trend, as compared to the current and UV absorption behaviour as a function of the varying [RF]. Owing to the intense PL characteristic of RF, the DNA lattices and thin films with RF might offer immense potential to develop efficient bio-sensors and useful bio-photonic devices.


Sign in / Sign up

Export Citation Format

Share Document