Showing papers on "Atomic layer deposition published in 1990"

Thin films by chemical vapour deposition

Abstract: The explosive growth in the semiconductor industry has caused a rapid evolution of thin film materials that lend themselves to the fabrication of state-of-the-art semiconductor devices. Early in the 1960s an old research technique named chemical vapour phase deposition (CVD), which has several unique advantages, developed into the most widely used technique for thin film preparation in electronics technology. In the last 25 years, tremendous advances have been made in the science and technology of thin films prepared by means of CVD. This book presents in a single volume, an up-to-date overview of the important field of CVD processes which has never been completely reviewed previously. Contents: Part I. 1. Evolution of CVD Films. Introductory remarks. Short history of CVD thin films. II. Fundamentals. 2. Techniques of Preparing Thin Films. Electrolytic deposition techniques. Vacuum deposition techniques. Plasma deposition techniques. Liquid-phase deposition techniques. Solid-phase deposition techniques. Chemical vapour conversion of substrate. Chemical vapour deposition. Comparison between CVD and other thin film deposition techniques. 3. Chemical Processes Used in CVD.

Novel Precursors for the Deposition of II-VI Semiconductor Films

Abstract: Highly sterically hindered chalcogenolato complexes M(EC6H2R3-2,4,6)2 (M = Zn, Cd, Hg; E = S, Se, Te; R = Me, Pri, But) have been prepared. Compounds with R = But are volatile under reduced pressure and are suitable as precursors for the deposition of II-VI films.

Laser Deposition of Molybdenum Oxide Thin Films From Organometallic Precursors

Abstract: Thin films of crystalline molybdenum oxides were formed on silicon surfaces by laser deposition. An ArF excimer laser was used to photodissociate molybdenum hexacarbonyl in an oxygen-containing ambient. Normal incidence of the laser led to the formation of very thin (< 1000 A) films of crystalline MO4O11. The films were characterized by color, SEM, Raman spectroscopy, and X-ray diffraction.

Ferroelectric Thin Films by Metal Organic Chemical Vapour Deposition

Abstract: There is a growing interest in thin films of ferroelectric oxides because of their electronic and optoelectronic applications. Various growth processes are being explored, but here, we review progress with chemical vapour deposition in a purpose built low pressure reactor. The two ferroelectric perovskites selected for our initial studies were lead titanate and lead scandium tantalate which have necessitated the synthesis of proprietary precursors. These compounds are based on metal alkoxides and β-diketonates, and are suitably modified to exhibit the required volatility and necessary thermal and hydrolytic stabilities. Deposition has been studied over the temperature range 400—8000C and, in general, amorphous films result which can be converted by subsequent annealing to crystalline perovskites. However, the inclusion of hydroxyl group compounds (H20 or alcohols) in the vapour train catalyses the crystallisation process and enhances the growth rates at temperatures in excess of 600°C. In order to deposit the perovskite phase, it is important to maintain the gas phase composition throughout the growth. Deposition rates of up to lOμm/hour can be achieved, but the best thin films, in terms of density and morphology, are formed at lower deposition rates. The crystallite size of the deposit may vary from O.lμm up to 2μm, depending on temperature. The choice of precursors, gas compositions and the growth conditions will be discussed in conjunction with the electrical and structural properties of the layers grown.

Formation Of Silicon-Based Heterostructures In Multichamber Integrated-Processing Thin-Film Deposition Systems

Abstract: This paper describes the formation of heterostructure devices using multichamber, integrated-processing thin-film deposition systems with UHV-compatible inter-chamber transfer. We describe the application of remote plasma-enhanced chemical-vapor deposition (Remote PECVD) for deposition of semiconducting and dielectric thin films in representative device structures. Special attention is directed to: i) deposition conditions necessary for control of thin-film and interface chemistry; and ii) post-deposition-annealing for the stabilization of physical and electronic properties of the heterostructures, including the interfaces between the constituent layers.

Physics Of In-Situ Laser Deposition Of Superconducting Thin Films

Abstract: The physics of the in-situ laser deposition process is reviewed. Emphasis will be placed on the use of excimer lasers, and the deposition of YBCO thin films. It will be shown that the laser target interaction conditions, and the properties of the laser generated plume are inducive to the formation of high quality films. In addition to the formation of energetic atomic beams, laser deposition is also highly compatible with reactive deposition which make it suitable for oxide and nitride films. An in-situ diagnostic technique is introduced which is capable of detecting the inter-facial boundary layer between the film and the substrate. It is also shown that post-deposition in-situ oxidation is necessary for the formation of superconducting films.

Ion‐assisted deposition effects on the surface structure of a TiO2 thin film

Abstract: In this paper we present a comparison between the structure and roughness of two TiO2 thin films evaporated without and with ion bombardment, respectively. It is found that both their structure and their roughness are very different. Indeed, the film evaporated with ion bombardment exhibits a very smooth background with deep funnel shaped holes, while the other film surface proves to be both rough and rolling.

Method of forming insulating thin film

Abstract: PURPOSE: To form a dense insulating film of good quality having tight adhesion to the underlay and good step coverage by an atomic layer deposition process in which an object is exposed to molecular flows of different material gases several times CONSTITUTION: A gate electrode G of titanium film 11 is formed on a glass substrate 1 A layer is formed under a gate bus line GB, above which an aluminum film 12 is formed A thin Al 2 O 3 film 21 is formed under a gate insulating film 2 and an inner insulating film 8 by an ALE process A silicon nitride film 22 is formed on the thin film 21 by P-CVD An amorphous silicon layer 3, as the active semiconductor layer of a thin-film transistor, is continuously formed by P-CVD, and then there are formed an n + amorphous silicon layer 4 as a contact layer, and a channel protecting film 6 of SiO 2 Titanium film 5 is formed to make a source electrode S, a drain electrode D, and a drain bus line DB A display electrode E of ITO film is formed, and finally the substrate is entirely covered with surface protecting film 7 of Al 2 O 3 by an ALE process COPYRIGHT: (C)1991,JPO&Japio

The application of plasmas to thin film deposition processes

Abstract: The plasma environment can play an important role in the deposition of thin films. The plasma can alter the nature and chemistry of species in the plasma, provide ions for bombardment of surfaces and “activate” species for reactive deposition processes. Each of these effects can change the properties of the resulting film material. The changes may be desirable or undesirable and their control requires an understanding of the processes involved.

Preparation of high Tc YBa2Cu3O7-x thin films

Abstract: The various deposition processes for preparing high-T superconducting thin flints are compared. The focus is on both the key film properties produced by each technique as well as the advantages and disadvantages of the specific deposition process. Emphasis is placed on the issues relating to film manufacturability and consequently centers on the YBaCu3O7 superconductor. Innovative solutions allowing in-situ fabrication of thin films are also covered along with the leading post-anneal processes. The specific techniques examined include sputtering (single-target and multi-target), electron-beam co-evaporation, MBE, laser ablation, ion-beam deposition, and CVD.

Fabrication technique of silicon power devices by liquid phase epitaxy

Abstract: Investigations have been made of the compensation effect of lattice constant on LPE grown silicon layer by simultaneous doping of tin and phosphorus. It is possible to reduce the strain by proper doping of tin, and highly doped layer can be grown on the highly resistive substrate under lattice matching condition. We have presented the principle of the yoyo solute feeding method. The Bipolar-Mode SIT could be fabricated by yo-yo method. We confirm that the yo-yo method using the compensation effect is the promising technique for fabrication of the silicon power devices,

Laser-Induced Chemical Vapour Deposition of Thin Films in Microelectronics

Abstract: Lateral thin film structures of Si, Mo, W, Co and TiSi2 can be generated by laser-induced pyrolytical and/or photolytical chemical vapour deposition techniques (LCVD) using perpendicular incident focused laser light. The process, and film parameters, e. g. growth rate, film width, crystalline structure, and specific resistance have been investigated and compared with a mathematical model.