Papers by Keyword: Rapid Thermal Annealing

Abstract: Indium tin oxide (ITO) thin films with 100 nm thickness were successfully deposited on soda-lime glass substrates by metal oxide electron beam evaporation at room temperature. The deposited films were post annealed via rapid thermal processor (RTP) in vacuum environment at 400 to 550 °C. All deposited ITO thin films were studied on the structural, electrical, and optical properties. Results showed that the post annealing treatment by RTP improved the crystallinity, increased crystallite size, and increased surface roughness values. Higher RTP post annealing temperature also enhanced the electrical performance that led to higher transmittance of ITO thin films.

Abstract: The application of special nanomaterials is promising for the development of new methods for the diagnostics and treatment of cancer. Photodynamic therapy (PDT) is a well-known and recognized method of cancer treatment. This type of therapy is less carcinogenic and mutagenic compared to radiation and chemotherapy, since the applied photosensitizers do not bind to DNA of the cells. However, currently this technique is only applicable to skin cancer, while its extension to the treatment of abdominal tumors requires the creation of pharmacological drugs for PDT, which along with a photosensitizer include a colloidal solution of nanosized luminescent phosphor emitting visible light with the required wavelength under the influence of infrared, X-ray or γ-radiation, which easily penetrates the body tissues. Since photosensitizers are already available as commercial products, the most important goal is the development of nanosized phosphors providing the required radiation convertion. In this study, the effects of hydrothermal synthesis, duration and the conditions of rapid thermal annealing (RTA) on Y₂O₃:Eu phosphor particle size were studied. The hydrothermal synthesis technique was carried out in two ways: chloride (precipitation from a chloride solution using NaOH and NH₄OH precipitators) and acetate (decomposition of mixed acetate either without a dispersant at 230° C for 24 hours, or using PEG-200 and PEG-2000 as dispersants at 230 °C for 12 hours). The rapid thermal annealing was performed either at 600 °C for 20 minutes, or at 800 °C for 5 minutes. The developed synthetic approaches afforded Y₂O₃:Eu nanosized phosphor samples with the particle size not exceeding 200 nm.

Abstract: Metallic nanoparticles have various potential applications. Recent studies have showed that their morphology had a strong influence on their optical and electrical properties. In this work, rapid thermal annealing was used to produce gold nanoparticles on silicon substrates. Morphology control of the gold nanoparticles was made by changing inert annealing gases. Spherical gold nanoparticles were obtained with nitrogen while hemispherical gold nanoparticles were formed with argon.

Abstract: Indium doped tin oxide (ITO) thin films were deposited on silicon wafer (100) and glass slide by ion assisted electron beam evaporation deposition. After deposition, the ITO thin films were annealed in vacuum (100-300°C) and their structural, optical and electrical properties were systematically investigated. X-ray diffraction,atomic force microscopy, ultraviolet–visible (UV–vis) spectrophotometer and hall-effect measurement were employed to obtain information on the crystallization, transmission and resistivity the films.It was found that the rapid thermal annealing can improve the resistivity of ITO thin films which specializes for the transparent conductive layers.

Abstract: Elimination of basal plane dislocations (BPDs) in epitaxial 4H-SiC is demonstrated via a novel pulsed annealing technique in a moderate N₂ overpressure of 0.55 MPa. BPD removal in 15 µm thick epitaxial 4H-SiC was confirmed using ultraviolet photoluminescence (UVPL) imaging before and after the annealing process. The samples were capped with a carbon cap, introduced into the annealing chamber, and brought up to a base temperature (T_BASE) of around 1550 °C for the pulsed anneal. The multicycle rapid thermal anneal (MRTA) was then performed in the T_BASE:T_MAX range, where T_MAX = 1875 °C was the peak temperature reached by the annealing cycles. Post-anneal surface quality and carrier lifetime were characterized by atomic force microscopy and time-resolved photoluminescence decay.

Abstract: Unintentionally doped GaSb films grown by Molecular Beam Epitaxy (MBE) on GaAs (001) substrates were annealed under different temperatures and time. It was found that the rapid thermal annealing (RTA) process can improve the optical properties. By changing annealing temperature and time, the optimized annealing temperature and times are found to be 650°C and 30s, respectively. Point defects and dislocations are two major kinds of defect in undoped GaSb thin films grown by MBE on GaAs (001) substrates.