摘要:

Cross‐sectional transmission electron microscopy (XTEM) has been used to investigate the effects of variations in the low‐energy ion irradiation flux during the growth of reactively sputter‐deposited TiN. The films were deposited on steel substrates with a negative bias of 100 V at 350 °C in mixed Ar–N2discharges at a pressure of 5 Pa (37 mTorr). The ion‐to‐Ti arrival rate ratio Jion/JTiat the substrate was varied between 0.3 and 7.1 through the use of a variable external magnetic field. Films grown with Jion/JTi≲2 had a columnar morphology with a highly underdense microstructure. Increasing Jion/JTi≳4 was sufficient to cause the growth of dense films with a more equiaxed grain structure due to renucleation. Further increases in Jion/JTi≳7 resulted in increased TiN grain size and local heteroepitaxy between TiN and the martensitic phase of the substrate.

ISSN:0734-2101    

DOI:10.1116/1.577428

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

This study deals with solid‐state phase transformations occurring at interfaces between a TiN film and an AISI M50 steel substrate during postdeposition annealing at 500 and 1000 °C. Cross‐sectional transmission electron microscopy (XTEM) was used to investigate the nature of phase transformations at these interfaces. The TiN films were ion plated onto M50 steel with an initial Ti underlayer at 100 °C. XTEM and electron energy loss spectroscopy of the interfaces indicated that the ion‐plated Ti underlayers transformed into a TiC phase during annealing at 500 °C and into a Ti(C,N) phase during annealing at 1000 °C. In addition, the density of defects within grains was significantly reduced during annealing and the grains themselves became larger.

ISSN:0734-2101    

DOI:10.1116/1.577429

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

We have used remote plasma‐enhanced chemical vapor deposition (remote PECVD) to deposit both intrinsic and doped μc‐Si thin films at temperatures between 100 and 400 °C. Two different deposition pathways have been studied: (i) plasma excitation of He/H2mixtures with downstream injection of silane, SiH4, and the dopant gases phosphine, PH3or diborane, B2H6; and (ii) plasma excitation of He, with downstream injection of SiH4and H2, as well as the dopant gases. We have observed that the second pathway, (ii) readily promotes nucleation of μc‐Si on a number of different substrate materials, including crystalline Si, fused silica, and silicon dioxide, SiO2, deposited by the remote PECVD process. The other pathway, with the H2coexcited with He, frequency results in the deposition of a thin amorphous silicon transition region between the substrate and the μc‐Si film, which then nucleates within thea‐Si material, rather than at the substrate itself. The properties of μc‐Si films deposited by remote PECVD have been characterized by Raman spectroscopy, transmission electron microscopy (TEM), dark conductivity, and photoconductivity.

ISSN:0734-2101    

DOI:10.1116/1.577430

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

Silicon carbide films were deposited by plasma enhanced chemical vapor deposition utilizing monomethylsilane (CH3SiH3). Silicon (100) and polycrystalline gold were used as substrates. A mass spectrometric analysis of the monomethylsilane plasma showed that the majority of the Si–C bonds were preserved in the gas phase. The composition, the density and morphology of the amorphous SiC:H (a:SiC:H) films were studied as a function of substrate temperature, composition of the ion flux bombarding the surface and the kinetic energy of these ions. The surface science techniques utilized for these investigations include x‐ray photoelectron spectroscopy, Auger electron spectroscopy, scanning electron microscopy, Fourier transform infrared, and Raman spectroscopies.

ISSN:0734-2101    

DOI:10.1116/1.577431

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

An investigation was made of Pt–Ir silicide films on (100)Si prepared by deposition of submonolayer thickness of Pt followed by 20–30 Å of Ir. Submonolayer coverages of Pt induce a crystalline texture approaching an epitaxial relationship between the normally amorphous IrSi film and the crystalline (100) Si substrate. Films were prepared usinge‐beam deposition, substrate temperature of 350 °C, and pressure at deposition ∼10−7Torr. Rutherford backscattering, transmission electron microscopy, and Auger electron spectroscopy are used to characterize composition and thickness. Grain structure and crystallinity as well as film and substrate interface characteristics are functions of predeposition conditions. Simple diode measurements illustrate the effect of predeposited Pt on the emission coefficient and cutoff wavelength. Data suggests a model where the predeposited Pt acts as nucleation sites for crystal growth.

ISSN:0734-2101    

DOI:10.1116/1.577432

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

V2O3is a phase transition material, which, like other oxides of vanadium, undergoes large changes in optical and electrical properties upon switching from the semiconductor to metal state. The transition in V2O3occurs at temperatures well below that of oxides in the same family, namely near 150–170 K, making it attractive for a number of low‐temperature applications. This material has been deposited by a variety of methods, including chemical vapor transport, rf sputtering of a stoichiometric target, pyrolysis, and heat treatment of a sputtered vanadium oxide film. Thin films of this material have also been prepared by the reduction of predeposited VO2thin films, requiring the flow of hazardous gases such as hydrogen or carbon monoxide over the sample, which is held at high temperatures in excess of 700 °C. A direct synthesis method for the deposition of high quality V2O3thin films with low infrared absorption and resistivity change of more than six orders of magnitude is described. Optical, resistivity, and morphological characteristics of this material are discussed.

ISSN:0734-2101    

DOI:10.1116/1.577389

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

A new coating system which generates a magnetically confined plasma via microwave heating in an electron cyclotron resonance zone has shown much promise in several coating applications. The system is used to produce high density plasmas of gas and/or metals ions. With metal plasmas, many of the deposited coatings are made exclusively from singly ionized, ion depositions. For many metals the system produces fairly high deposition rates (greater than 1 μ a min for many metals) using a sputter plate as the source of neutrals to be ionized. The use of evaporative neutral sources should produce higher densities and deposition rates. The operation of this system and its use in several interesting coating applications is discussed. These applications have included the generation of multilayered coatings for x‐ray optics, the effect of surface bias on metal ion depositions, low voltage (50 to 60 eV)/hi current (30 mA/cm2) sputter etching, and depositions from metal‐reactive gas plasmas.

ISSN:0734-2101    

DOI:10.1116/1.577390

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

The electronic and optical properties of device qualitya‐Si:H anda‐(Si,Ge):H films grown by remote plasma electron cyclotron resonance (ECR) deposition were studied together with the plasma characteristics during growth. 100–350 W microwave plasmas, which were formed by introducing hydrogen and helium into the ECR chamber, were used to decompose silane and germane downstream of the ECR source. Use of hydrogen allows selective etching of the growth surface by reactive ion species. The plasma properties near the deposition surface are characterized using movable plane and cylindrical Langmuir probes and are correlated with the light and dark photoconductivity, optical gap, stability, and silicon–hydrogen bonding distribution of the deposited film in an effort to understand the influence that plasma species have on film quality.

ISSN:0734-2101    

DOI:10.1116/1.577391

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

Good quality, low temperature silicon nitride and oxynitride films were deposited downstream from an electron cyclotron resonance (ECR) plasma source using SiH4and N2gas mixtures. The Si/N ratio and H content in the deposited films were determined using Rutherford backscattering spectrometry and elastic recoil detection. The H concentration was minimum for films with compositions closest to that of stoichiometric Si3N4. The optimum conditions for producing a stoichiometric Si3N4were a SiH4/N2flow ratio between 0.1 and 0.2, and an electrically isolated sample far from the ECR source. Infrared absorption spectra showed that as the film composition changed from N rich to Si rich the dominant bonds associated with H changed from N–H to Si–H.

ISSN:0734-2101    

DOI:10.1116/1.577392

出版商:American Vacuum Society    

年代:1991

数据来源: AIP

摘要:

RS/Discover, an experimental software package, was used to construct a Plackett‐Burman screening experiment to relate the film properties of a silane‐based undoped plasma‐enhanced chemical‐vapor deposited (PECVD) SiO2to the deposition parameters in a Novellus PECVD reactor. Temperature, pressure, power, and gas flows were simultaneously varied to study the effects that the deposition parameters had on the physical, chemical, and electrical film characteristics. A linear model was developed from the data collected. The Fourier transform infrared (FTIR) spectra revealed that the asymmetric Si–O–Si peak position correlated to several film parameters including the destructive breakdown voltage, the wet etch rate, and the index of refraction of the deposited oxide. The highest deposition rates (>0.6 μm/min) and film thickness uniformity (<1.0% nonuniformity) were obtained when the Novellus system was operated at high silane flows with low power and pressure values. The particulate level was found to be directly related to the nitrogen carrier gas flow rate.

ISSN:0734-2101    

DOI:10.1116/1.577393

出版商:American Vacuum Society    

年代:1991

数据来源: AIP