Showing papers on "Silicon nitride published in 2003"

Etch rates for micromachining processing-Part II

Abstract: Samples of 53 materials that are used or potentially can be used or in the fabrication of microelectromechanical systems and integrated circuits were prepared: single-crystal silicon with two doping levels, polycrystalline silicon with two doping levels, polycrystalline germanium, polycrystalline SiGe, graphite, fused quartz, Pyrex 7740, nine other preparations of silicon dioxide, four preparations of silicon nitride, sapphire, two preparations of aluminum oxide, aluminum, Al/2%Si, titanium, vanadium, niobium, two preparations of tantalum, two preparations of chromium, Cr on Au, molybdenum, tungsten, nickel, palladium, platinum, copper, silver, gold, 10 Ti/90 W, 80 Ni/20 Cr, TiN, four types of photoresist, resist pen, Parylene-C, and spin-on polyimide. Selected samples were etched in 35 different etches: isotropic silicon etchant, potassium hydroxide, 10:1 HF, 5:1 BHF, Pad Etch 4, hot phosphoric acid, Aluminum Etchant Type A, titanium wet etchant, CR-7 chromium etchant, CR-14 chromium etchant, molybdenum etchant, warm hydrogen peroxide, Copper Etchant Type CE-200, Copper Etchant APS 100, dilute aqua regia, AU-5 gold etchant, Nichrome Etchant TFN, hot sulfuric+phosphoric acids, Piranha, Microstrip 2001, acetone, methanol, isopropanol, xenon difluoride, HF+H/sub 2/O vapor, oxygen plasma, two deep reactive ion etch recipes with two different types of wafer clamping, SF/sub 6/ plasma, SF/sub 6/+O/sub 2/ plasma, CF/sub 4/ plasma, CF/sub 4/+O/sub 2/ plasma, and argon ion milling. The etch rates of 620 combinations of these were measured. The etch rates of thermal oxide in different dilutions of HF and BHF are also reported. Sample preparation and information about the etches is given.

Measuring Thermal and Thermoelectric Properties of One-Dimensional Nanostructures Using a Microfabricated Device

Abstract: We have batch-fabricated a microdevice consisting of two adjacent symmetric silicon nitride membranes suspended by long silicon nitride beams for measuring thermophysical properties of one-dimensional manostructures (nanotubes, nanowires, and mmobelts) bridging the two membranes. A platinum resistance heater/thermometer is fabricated on each membrane. One membrane can be Joule heated to cause heat conduction through the sample to the other membrane. Thermal conductance, electrical conductance, and Seebeck coefficient can be measured using this microdevice in the temperature range of 4-400 K of an evacuated Helium cryostat. Measurement sensitivity, errors, and uncertainty are discussed. Measurement results of a 148 nm and a 10 nm-diameter single wall carbon nanotube bundle are presented.

Advances in microstructure and mechanical properties of zirconium diboride based ceramics

Abstract: The use of silicon nitride as a sintering aid (5 vol.%) greatly improves the powder sinterability of zirconium diboride, in comparison to additive free ZrB2. Nearly full dense monolithic material is obtained by hot pressing at 1700 °C. The microstructure consists of fine regular ZrB2 grains and of various secondary grain boundary phases (e.g. BN, t-ZrO2, BN-rich glassy phase), mainly located at triple points. The addition of 20 vol.% of silicon carbide as a reinforcing particulate phase to the ZrB2+5vol.%Si3N4 powder mixture slows down the densification rate of ZrB2, therefore a higher hot pressing temperature (i.e. 1870 °C) is necessary to achieve nearly full density. Further addition of oxide additives (1vol.%Al2O3+0.5vol.%Y2O3) to the ZrB2–20vol.%SiC–5vol.%Si3N4 system enables the production of near fully dense composites at lower hot pressing temperature (1760 °C). The presence of SiC particles in both the ZrB2-based composites effectively improves strength, hardness and toughness, compared to monolithic zirconium diboride. Some mechanical properties are very interesting: flexural strength up to 700 and 600 MPa are measured at room temperature and 1000 °C, respectively. The properties are discussed in terms of the microstructural features.

Handbook of Infrared Spectroscopy of Ultrathin Films

Abstract: PrefaceAcronyms and SymbolsIntroduction1 Absorption and Reflection of Infrared Radiation byUltrathin Films11 Macroscopic Theory of Propagation of ElectromagneticWaves in Infinite Medium12 Modeling Optical Properties of a Material13 Classical Dispersion Models of Absorption14 Propagation of IR Radiation through Planar Interface between Two Isotropic Media141 Transparent Media142 General Case15 Reflection of Radiation at Planar Interface Covered by Single Layer16 Transmission of Layer Located at Interface between Two Isotropic Semi-infinite Media17 System of Plane-Parallel Layers: Matrix Method18 Energy Absorption in Layered Media181 External Reflection: Transparent Substrates182 External Reflection: Metallic Substrates183 ATR19 Effective Medium Theory110 Diffuse Reflection and TransmissionAppendixReferences2 Optimum Conditions for Recording Infrared Spectra of Ultrathin Films21 IR Transmission Spectra Obtained in Polarized Radiation22 IRRAS Spectra of Layers on Metallic Surfaces ("Metallic" IRRAS)23 IRRAS of Layers on Semiconductors and Dielectrics231 Transparent and Weakly Absorbing Substrates ("Transparent" IRRAS)232 Absorbing Substrates233 Buried Metal Layer Substrates (BML-IRRAS)24 ATR Spectra25 IR Spectra of Layers Located at Interface251 Transmission252 Metallic IRRAS253 Transparent IRRAS254 ATR26 Choosing Appropriate IR Spectroscopic Method for Layer on Flat Surface27 Coatings on Powders, Fibers, and Matte Surfaces271 Transmission272 Diffuse Transmittance and Diffuse Reflectance273 ATR274 Comparison of IR Spectroscopic Methods for Studying Ultrathin Films on PowdersReferences3 Interpretation of IR Spectra of Ultrathin Films31 Dependence of Transmission, ATR, and IRRAS Spectra of Ultrathin Films on Polarization (Berreman Effect)32 Theory of Berreman Effect321 Surface Modes322 Modes in Ultrathin Films323 Identification of Berreman Effect in IR Spectra of Ultrathin Films33 Optical Effect: Film Thickness, Angle of Incidence, and Immersion331 Effect in "Metallic" IRRAS332 Effect in "Transparent" IRRAS333 Effect in ATR Spectra334 Effect in Transmission Spectra34 Optical Effect: Band Shapes in IRRAS as Function of Optical Properties of Substrate35 Optical Property Gradients at Substrate-Layer Interface: Effect on Band Intensities in IRRAS36 Dipole-Dipole Coupling37 Specific Features in Potential-Difference IR Spectra of Electrode-Electrolyte Interfaces371 Absorption Due to Bulk Electrolyte372 (Re)organization of Electrolyte in DL373 Donation/Backdonation of Electrons374 Stark Effect375 Bipolar Bands376 Effect of Coadsorption377 Electronic Absorption378 Optical Effect38 Interpretation of Dynamic IR Spectra: Two-Dimensional Correlation Analysis39 IR Spectra of Inhomogeneous Films and Films on Powders and Rough Surfaces Surface Enhancement391 Manifestation of Particle Shape in IR Spectra392 Coated Particles393 Composite, Porous, and Discontinuous Films394 Interpretation of IR Surface-Enhanced Spectra395 Rough Surfaces310 Determination of Optical Constants of Isotropic Ultrathin Films: Experimental Errors in ReflectivityMeasurements311 Determination of Molecular Packing and Orientation in Ultrathin Films: Anisotropic Optical Constants of Ultrathin Films3111 Order-Disorder Transition3112 Packing and Symmetry of Ultrathin Films3113 Orientation3114 Surface Selection Rule for Dielectrics3115 Optimum Conditions for MO StudiesReferences4 Equipment and Techniques 30741 Techniques for Recording IR Spectra of Ultrathin Films on Bulk Samples411 Transmission and Multiple Transmission412 IRRAS413 ATR414 DRIFTS42 Techniques for Ultrathin Films on Powders and Fibers421 Transmission422 Diffuse Transmission423 Diffuse Reflectance424 ATR43 High-Resolution FTIR Microspectroscopy of Thin Films431 Transmission432 IRRAS433 DRIFTS and DTIFTS434 ATR435 Spatial Resolution and Smallest Sampling Area436 Comparison of -FTIR Methods44 Mapping, Imaging, and Photon Scanning Tunneling Microscopy45 Temperature-and-Environment Programmed Chambers for In Situ Studies of Ultrathin Films on Bulk and Powdered Supports46 Technical Aspects of In Situ IR Spectroscopy of Ultrathin Films at Solid-Liquid and Solid-Solid Interfaces461 Transmission462 In Situ IRRAS463 ATR464 Measurement Protocols for SEC Experiments47 Polarization Modulation Spectroscopy48 IRRAS of Air-Water Interface49 Dynamic IR Spectroscopy491 Time Domain492 Frequency Domain: Potential-Modulation Spectroscopy410 Preparation of Substrates4101 Cleaning of IREs4102 Metal Electrode and SEIRA Surfaces4103 BML SubstrateReferences5 Infrared Spectroscopy of Thin Layers in Silicon Microelectronics51 Thermal SiO2 Layers52 Low-Temperature SiO2 Layers53 Ultrathin SiO2 Layers54 Silicon Nitride, Oxynitride, and Carbon Nitride Layers55 Amorphous Hydrogenated Films551 a-Si:H Films552 a-SiGe:H553 a-SiC:H Films56 Films of Amorphous Carbon, Boron Nitride, and Boron Carbide561 Diamondlike Carbon562 Boron Nitride and Carbide Films57 Porous Silicon Layers58 Other Dielectric Layers Used in Microelectronics581 CaF2, BaF2, and SrF2 Layers582 GeO2 Film583 Metal Silicides584 Amorphous Ta2O5 Films585 SrTiO3 Film586 Metal Nitrides59 Multi- and Inhomogeneous Dielectric Layers: Layer-by-Layer EtchingReferences6 Application of Infrared Spectroscopy to Analysis of Interfaces and Thin Dielectric Layers in Semiconductor Technology61 Ultrathin Oxide Layers in Silicon Schottky-Type Solar Cells62 Control of Thin Oxide Layers in Silicon MOS Devices621 CVD Oxide Layers in Al-SiOx -Si Devices622 Monitoring of Aluminum Corrosion Processes in Al-PSG Interface623 Determination of Metal Film and Oxide Layer Thicknesses in MOS Devices63 Modification of Oxides in Metal-Same-Metal Oxide-InP Devices64 Dielectric Layers in Sandwiched Semiconductor Structures641 Silicon-on-Insulator642 Polycrystalline Silicon-c-Si Interface643 SiO2 Films in Bonded Si Wafers644 Quantum Wells65 IR Spectroscopy of Surface States at SiO2 -Si Interface66 In Situ Infrared Characterization of Si and SiO2 Surfaces661 Monitoring of CVD of SiO2662 Cleaning and Etching of Si Surfaces663 Initial Stages of Oxidation of H-Terminated Si SurfaceReferences7 Ultrathin Films at Gas-Solid, Gas-Liquid, and Solid-Liquid Interfaces71 IR Spectroscopic Study of Adsorption from Gaseous Phase: Catalysis711 Adsorption on Powders712 Adsorption on Bulk Metals72 Native Oxides: Atmospheric Corrosion and Corrosion Inhibition73 Adsorption on Flat Surfaces of Dielectrics and Semiconductors74 Adsorption on Minerals: Comparison of Data Obtained In Situ and Ex Situ741 Characterization of Mineral Surface after Grinding: Adsorption of Inorganic Species742 Adsorption of Oleate on Calcium Minerals743 Structure of Adsorbed Films of Long-Chain Amines on Silicates744 Interaction of Xanthate with Sulfides75 Electrochemical Reactions at Semiconducting Electrodes: Comparison of Different In Situ Techniques751 Anodic Oxidation of Semiconductors752 Anodic Reactions at Sulfide Electrodes in Presence of Xanthate76 Static and Dynamic Studies of Metal Electrode-Electrolyte Interface: Structure of Double Layer77 Thin Polymer Films, Polymer Surfaces, and Polymer-Substrate Interface78 Interfacial Behavior of Biomolecules and Bacteria781 Adsorption of Proteins and Model Molecules at Different Interfaces782 Membranes783 Adsorption of BiofilmsReferencesAppendixReferencesIndex

Method to form ultra high quality silicon-containing compound layers

Abstract: Multiple sequential processes are conducted in a reaction chamber to form ultra high quality silicon-containing compound layers, including silicon nitride layers. In a preferred embodiment, a silicon layer is deposited on a substrate using trisilane as the silicon precursor. A silicon nitride layer is then formed by nitriding the silicon layer. By repeating these steps, a silicon nitride layer of a desired thickness is formed.

Morphology and electronic transport of polycrystalline pentacene thin-film transistors

Abstract: Temperature-dependent measurements of thin-film transistors were performed to gain insight in the electronic transport of polycrystalline pentacene. Devices were fabricated with plasma-enhanced chemical vapor deposited silicon nitride gate dielectrics. The influence of the dielectric roughness and the deposition temperature of the thermally evaporated pentacene films were studied. Although films on rougher gate dielectrics and films prepared at low deposition temperatures exhibit similar grain size, the electronic properties are different. Increasing the dielectric roughness reduces the free carrier mobility, while low substrate temperature leads to more and deeper hole traps.

High-efficiency visible photoluminescence from amorphous silicon nanoparticles embedded in silicon nitride

Abstract: Confinement of silicon nanoparticles in silicon nitride instead of an oxide matrix might materially facilitate its potential applications as a light-emitting component in optoelectronics. We report in this letter the production of high-density (up to 4.0×1012/cm2 from micrographs) silicon nanoparticles in SiNx thin films by chemical vapor deposition on cold substrates. Strong room-temperature photoluminescence was observed in the whole visible light range from the deposits that were postannealed at 500 °C for 2 min. The Si-in-SiNx films provide a significantly more effective photoluminescence than Si-in-SiOx fabricated with similar processing parameters: for blue light, the external quantum efficiency is over three times as large. The present results demonstrate that the nanostructured Si-in-SiNx system can be a very competitive candidate for the development of tunable high-efficiency light-emitting devices.

Method of fabricating silicon nitride nanodots

Abstract: A method of forming silicon nitride nanodots that comprises the steps of forming silicon nanodots and then nitriding the silicon nanodots by exposing them to a nitrogen containing gas. Silicon nanodots were formed by low pressure chemical vapor deposition. Nitriding of the silicon nanodots was performed by exposing them to nitrogen radicals formed in a microwave radical generator, using N2 as the source gas.

Method to plasma deposit on organic polymer dielectric film

Abstract: A method for protecting an organic polymer underlayer during a plasma assisted process of depositing a subsequent film on the organic polymer underlayer is disclosed. The method provides the deposition of a protective continuous layer using organic polymer damage-free technique in order to not damage the organic polymer underlayer and to protect the organic polymer underlayer during the plasma assisted process of depositing a subsequent film. The organic polymer damage-free technique is a non-plasma process, using only thermal energy and chemical reactions to deposit the continuous layer. The organic polymer damage-free technique can also be a plasma assisted process using a reduced plasma power low enough in order to not damage the organic polymer underlayer. This method is applicable to many organic polymer underlayers such as organic polymer is aromatic hydrocarbon, polytetrafluoroehtylene (PTFE), parylene, benzocyclobutene-based polymers (BCB), polyimide, fluorinated polyimide, fluorocarbon-based polymers, poly(arylene ether)-based polymers (PAE), cyclohexanone-based polymers, and to many plasma assisted deposition processes such as plasma enhanced CVD deposition, plasma enhanced ALD deposition and plasma enhanced NLD deposition of silicon dioxide, silicon nitride, nitrided diffusion barrier such as TiN, TaN, WN, TiSiN, TaSiN, WSiN.

Semiconductor device and method of manufacturing the same

Abstract: A semiconductor device has a pair of impurity regions in a semiconductor substrate. A silicon layer is formed on the impurity region. A gate insulating film is formed between the impurity regions. A gate electrode is formed on the gate insulating film. A first silicon nitride film is formed on the gate electrode. A silicon oxide film is formed on a side surface of the gate electrode. A second silicon nitride film is partially formed on the silicon layer and on a side surface of the silicon oxide film. A conductive layer is formed on the silicon layer.

SOI substrate, element substrate, semiconductor device, electro-optical apparatus, electronic equipment, method of manufacturing the SOI substrate, method of manufacturing the element substrate, and method of manufacturing the electro-optical apparatus

Abstract: An SOI (Silicon On Insulator) substrate is provided with: a support substrate ( 201 ); a single crystal silicon layer ( 202 ) disposed above one surface of the support substrate; an insulation portion ( 205 ) disposed between the support substrate and the single crystal silicon layer, the insulation portion comprising a single layer of an insulation film or a lamination structure of a plurality of insulation films, and including a silicon nitride film or a silicon nitride oxide film ( 204 ).

Cvd method and device for forming silicon-containing insulation film

Abstract: A CVD apparatus (2) forms an insulating film, which is a silicon oxide film, silicon nitride film, or silicon oxynitride film. The CVD apparatus includes a process chamber (8) to accommodate a target substrate (W), a support member (20) to support the target substrate in the process chamber, a heater (12) to heat the target substrate supported by the support member, an exhaust section (39) to vacuum-exhaust the process chamber, and a supply section (40) to supply a gas into the process chamber. The supply section includes a first circuit (42) to supply a first gas of a silane family gas, a second circuit (44) to supply a second gas, which is an oxidizing gas, nitriding gas, or oxynitriding gas, and a third circuit (46) to supply a third gas of a carbon hydride gas, and can supply the first, second, and third gases together.

Plasma-enhanced chemical vapor deposited silicon carbide as an implantable dielectric coating.

Abstract: Amorphous silicon carbide (a-SiC) films, deposited by plasma-enhanced chemical vapor deposition (PECVD), have been evaluated as insulating coatings for implantable microelectrodes. The a-SiC was deposited on platinum or iridium wire for measurement of electrical leakage through the coating in phosphate-buffered saline (PBS, pH 7.4). Low leakage currents of <10(-11) A were observed over a +/-5-V bias. The electronic resistivity of a-SiC was 3 x 10(13) Omega-cm. Dissolution rates of a-SiC in PBS at 37 and 90 degrees C were determined from changes in infrared absorption band intensities and compared with those of silicon nitride formed by low-pressure chemical vapor deposition (LPCVD). Dissolution rates of LPCVD silicon nitride were 2 nm/h and 0.4 nm/day at 90 and 37 degrees C, respectively, while a-SiC had a dissolution rate of 0.1 nm/h at 90 degrees C and no measurable dissolution at 37 degrees C. Biocompatibility was assessed by implanting a-SiC-coated quartz discs in the subcutaneous space of the New Zealand White rabbit. Histological evaluation showed no chronic inflammatory response and capsule thickness was comparable to silicone or uncoated quartz controls. Amorphous SiC-coated microelectrodes were implanted in the parietal cortex for periods up to 150 days and the cortical response evaluated by histological evaluation of neuronal viability at the implant site. The a-SiC was more stable in physiological saline than LPCVD Si(3)N(4) and well tolerated in the cortex.

Micromachined ultrasonic transducers and method of fabrication

Abstract: There is described a micromachined ultrasonic transducers (MUTS) and a method of fabrication. The membranes of the transducers are fusion bonded to cavities to form cells. The membranes are formed on a wafer (11) of sacrificial material. This permits handling for fusions bonding. The sacrificial material is then removed to leave the membrane (14). Membranes of silicon, silicon nitride, etc. can be formed on the sacrificial material. Also described are cMUTs, pMUTs and mMUTs.

Semiconductor device fabrication method

Abstract: A reduction of a leakage current as well as a decrease in the thickness of an insulating film is realized in a semiconductor device. To this end, a silicon oxide film and a silicon nitride film are formed on a substrate, which is then heated to a temperature within a range of 20° C.-600° C. so that a plasma nitridation process can be performed on the silicon nitride film. Further, a thermal process is performed in a non-oxide gas atmosphere. By performing these processes, the gate leakage current can be significantly reduced in the formed gate insulator, and the silicon oxide-equivalent thickness of the insulating film can be significantly decreased as well.

Insulating layers in semiconductor devices having a multi-layer nanolaminate structure of SiNx thin film and BN thin film and methods for forming the same

Abstract: The present invention discloses a novel insulating layer for use in semiconductor devices, the insulating layer having a multi-layer nanolaminate structure consisting of alternating boron nitride thin films and silicon nitride thin films, each of a controlled, desired thickness, together with methods for forming the same The insulating layer of the present invention has a multi-layer nanolaminate structure consisting of alternating boron nitride thin films and silicon nitride thin filmsformed by the steps of: (a) depositing a silicon nitride thin film on a wafer, (b) depositing a boron nitride thin film on the silicon nitride thin film, and (c) forming the multi-layer nanolaminate thin film by alternately repeating steps (a) and (b)

Method and apparatus for forming a high quality low temperature silicon nitride layer

Abstract: A method of forming a silicon nitride film is described. According to the present invention, a silicon nitride film is deposited by thermally decomposing a silicon/nitrogen containing source gas or a silicon containing source gas and a nitrogen containing source gas at low deposition temperatures (e.g., less than 550°C) to form a silicon nitride film. The thermally deposited silicon nitride film is then treated with hydrogen radicals to form a treated silicon nitride film.

Methods of etching silicon nitride substantially selectively relative to an oxide of aluminum

Abstract: A method of etching silicon nitride substantially selectively relative to an oxide of aluminum includes providing a substrate comprising silicon nitride and an oxide of aluminum. The silicon nitride and the oxide is exposed to an etching solution comprising HF and an organic HF solvent under conditions effective to etch the silicon nitride substantially selectively relative to the oxide. Other aspects and implementations are contemplated.

Use of nitrides for flip-chip encapsulation

Abstract: A hermetically sealed semiconductor flip chip and its method of manufacture is disclosed. The semiconductor flip chip of the present invention is sealed with a silicon nitride layer on an active surface of the flip chip. The silicon nitride layer covers the chip active surface, including bond pads and conductive connectors such as solder balls formed over the bond pads to effect electrical and mechanical connection to terminal pads of a carrier substrate. A portion of the silicon nitride layer is penetrated or removed to expose a portion of each conductive connector. The flip chip is then attached to a substrate by contact of the exposed portions of the conductive connectors with the terminal pads of the substrate. Also included in the invention is the alternative of sealing the flip chip, substrate and intervening connectors with a silicon nitride layer after the attachment of the flip chip to the substrate.

Mechanical properties of sputtered silicon nitride thin films

Abstract: Silicon nitride thin films were prepared by reactive sputtering from different sputtering targets and using a range of Ar/N2 sputtering gas mixtures. The hardness and the Young’s modulus of the samples were determined by nanoindentation measurements. Depending on the preparation parameters, the obtained values were in the ranges 8–23 and 100–210 GPa, respectively. Additionally, Fourier-transform infrared spectroscopy, Rutherford backscattering spectroscopy, and x-ray diffraction were used to characterize samples with respect to different types of bonding, atomic concentrations, and structure of the films to explain the variation of mechanical properties. The hardness and Young’s modulus were determined as a function of film composition and structure and conditions giving the hardest film were found. Additionally, a model that assumes a series coupling of the elastic components, corresponding to the Si–O and Si–N bonds present in the sample has been proposed to explain the observed variations of hardness and Young’s modulus.

Methods for producing silicon nitride films and silicon oxynitride films by thermal chemical vapor deposition

Abstract: To provide a CVD-based method for the relatively low temperature production of silicon nitride films and silicon oxynitride films that exhibit excellent film properties wherein said method is not accompanied by the production of ammonium chloride. Gaseous aminosilane such as tris(isopropylamino)silane and a gaseous hydrazine compound such as dimethylhydrazine are fed into a chemical vapor deposition reaction chamber that holds at least one substrate and silicon nitride film is formed on the substrate by reacting the two gases in said chemical vapor deposition reaction chamber.

Passivation integrity improvements

Abstract: An exemplary implementation of the invention is a process for forming passivation protection on a semiconductor assembly by the steps of: forming a layer of oxide over patterned metal lines having sidewalls; forming a first passivation layer of silicon nitride over the layer of oxide such that the first passivation layer of silicon nitride resides along the sidewalls of metal lines and pinches off a gap between the metal lines; performing a facet etch to remove material from the edges of the first passivation layer of silicon nitride and re-deposits some of removed material across a pinch-off junction; forming a second passivation layer of silicon nitride on the first passivation layer of silicon nitride.

Influence of the high-temperature “firing” step on high-rate plasma deposited silicon nitride films used as bulk passivating antireflection coatings on silicon solar cells

Abstract: The influence of a short high-temperature step, comparable to the so-called “firing” of the metallization on silicon solar cells, on properties of high-rate (>0.5 nm/s) plasma deposited silicon nitride (a-SiNx:H) films has been investigated. These a-SiNx:H films are used as antireflection coating on multicrystalline silicon (mc-Si) solar cells and, after the firing process, they also induce hydrogen bulk passivation in the mc-Si. Three different types of remote plasma deposited a-SiNx:H films have been investigated: (i) expanding thermal plasma (ETP) deposited a-SiNx:H films from a N2–SiH4 gas mixture, (ii) ETP deposited a-SiNx:H films from a NH3–SiH4 mixture, and (iii) microwave plasma deposited a-SiNx:H films from a NH3–SiH4 mixture. The atomic composition and optical and structural properties of the films have been studied before and after the high-temperature step by the combination of elastic recoil detection, spectroscopic ellipsometry, and Fourier transform infrared spectroscopy. It has been observed that the high-temperature step can induce significant changes in hydrogen content, bonding types, mass density, and optical absorption of the films. These thermally induced effects are more enhanced for Si- than for N-rich films, which in some cases have a high thermal stability. Furthermore, the material properties and the influence of the high-temperature step have been related to the bulk passivation properties of the a-SiNx:H coated mc-Si solar cells. It is found that in particular the density and thermal stability of the a-SiNx:H films seem to be important for the degree of the bulk passivation obtained.

Deposition method of silicon nitride film

Abstract: PROBLEM TO BE SOLVED: To provide a method of depositing silicon nitride film of higher film quality even under lower processing temperature. SOLUTION: The silicon nitride (SiN) film is deposited on a substrate 6 with the silane (SiH 4 ) gas and nitride (N 2 ) gas used as the raw material gasses by utilizing an ICP type plasma CVD apparatus. In this case, the supply flow rate of nitrogen (N 2 ) gas is set to 10 times or more the flow rate of silane (SiH 4 ) gas, the radio frequency power for total supply flow rate of gasses (RF power: energy of electromagnetic wave inputted to a deposition chamber) is set to 3W/sccm or more, substrate temperature is set to 50 to 300°C, and deposition pressure is set to 10mTorr to 50mTorr. COPYRIGHT: (C)2005,JPO&NCIPI