Atomic layer deposition

About: Atomic layer deposition is a research topic. Over the lifetime, 19821 publications have been published within this topic receiving 477332 citations. The topic is also known as: ALD.

Charateristics of Low Temperature High Quality Silicon Oxide by Plasma Enhanced Atomic Layer Deposition with In Situ Plasma Densification Process

Abstract: We have researched low temperature silicon oxide (SiO2) with improved electrical properties and excellent film step-coverage. In-situ O2 plasma densification (DENSIFICATION) effect on SiO2 that has been deposited by PE-ALD at temperature (<400°C) was investigated. The wet etch rate was controllable as a function of DENSIFICAION time due to repairing of the SiO2 network defects by the oxygen radicals. Angle Resolved X-ray Photoelectron Spectroscopy (AR-XPS) analysis was carried out to observe the core-level binding energies shifts (chemical shifts) in the different SiO2 films. The characteristics of wet etch rate of high quality low temperature SiO2 demonstrated lower than high temperature LP-CVD SiO2 values. Compared to LP-CVD SiO2, PE-ALD SiO2 with DENSIFICATION showed excellent I-V characteristics with lower leakage current and similar to the thermal SiO2 carrier transport plot.

Method of forming ultrathin oxide layer

Abstract: A method is disclosed for forming an ultrathin oxide layer of uniform thickness. The method is particularly advantageous for producing uniformly thin interfacial oxides beneath materials of high dielectric permittivity, or uniformly thin passivation oxides. Hydrofluoric (HF) etching of a silicon surface, for example, is followed by termination of the silicon surface with ligands larger than H or F, particularly hydroxyl, alkoxy or carboxylic tails. The substrate is oxidized with the surface termination in place. The surface termination and relatively low temperatures moderate the rate of oxidation, such that a controllable thickness of oxide is formed. In some embodiments, the ligand termination is replaced with OH prior to further deposition. The deposition preferably includes alternating, self-limiting chemistries in an atomic layer deposition process, though any other suitable deposition process can be used. Two or more of the HF etching, surface termination, oxidation, hydroxyl replacement of the surface termination and deposition on the oxide can be conducted in situ.

Inversion channel diamond metal-oxide-semiconductor field-effect transistor with normally off characteristics

Abstract: We fabricated inversion channel diamond metal-oxide-semiconductor field-effect transistors (MOSFETs) with normally off characteristics. At present, Si MOSFETs and insulated gate bipolar transistors (IGBTs) with inversion channels are widely used because of their high controllability of electric power and high tolerance. Although a diamond semiconductor is considered to be a material with a strong potential for application in next-generation power devices, diamond MOSFETs with an inversion channel have not yet been reported. We precisely controlled the MOS interface for diamond by wet annealing and fabricated p-channel and planar-type MOSFETs with phosphorus-doped n-type body on diamond (111) substrate. The gate oxide of Al2O3 was deposited onto the n-type diamond body by atomic layer deposition at 300 °C. The drain current was controlled by the negative gate voltage, indicating that an inversion channel with a p-type character was formed at a high-quality n-type diamond body/Al2O3 interface. The maximum drain current density and the field-effect mobility of a diamond MOSFET with a gate electrode length of 5 μm were 1.6 mA/mm and 8.0 cm2/Vs, respectively, at room temperature.

Aerogel Templated ZnO Dye‐Sensitized Solar Cells

Abstract: Atomic layer deposition is employed to conformally coat low density, high surface area aerogel films with ZnO. The ZnO/aerogel membranes are incorporated as photoanodes in dye-sensitized solar cells, which exhibit excellent power efficiencies of up to 2.4% under 100 mW cm{sup -2} light intensity.

Systems and methods for forming strontium-and/or barium-containing layers

Abstract: A method of forming (and system for forming) layers, such as calcium, barium, strontium, and/or magnesium, tantalates and/or niobates, and optionally titanates, on a substrate by employing a vapor deposition method, particularly a multi-cycle atomic layer deposition process.