Laser Photochemical Vapour Deposition of Epitaxial Ge Films on GaAs from GeH4 Using NH3 as a Sensitiser

1988 ◽  
Vol 129 ◽  
Author(s):  
C.J. Kiely ◽  
C. Jones ◽  
V. Tavitian ◽  
J.G. Eden
Keyword(s):  
Growth Rate ◽  
Photoelectron Spectroscopy ◽  
Vapour Deposition ◽  
Film Growth ◽  
Hydrogen Abstraction ◽  
Auger Spectroscopy ◽  
Hydrogen Atoms ◽  
Production Of Hydrogen ◽  
Substrate Temperatures ◽  
Secondary Ion

ABSTRACTThe viability of ammonia as a sensitiser for the epitaxial growth of Ge on GaAs by laser photochemical vapour deposition (LPVD) has been investigated. Specifically NH3/GeH4/He (0.8/5/95 sccm, 5.5 Torr total pressure) mixtures have been irradiated by a 193nm ArF excimer laser in parallel geometry for substrate temperatures, Ts<400°C. As evidenced by a dramatic acceleration in Ge film growth rate, the NH3 efficiently couples the laser radiation to the GeH4 precursor molecule. The microstructures of LPVD Ge films grown with and without NH3 have been examined by TEM, and the epitaxial nature of both types of films has been verified, although some subtle differences are noted. Chemical analysis of the deposited films has been carried out using Auger spectroscopy, X-ray photoelectron spectroscopy and secondary ion mass spectroscopy. Our results show that there is little or no nitrogen incorporation into the Ge films grown in the presence of NH3, and that hydrogen contamination in our films is minimal. The beneficial effect of NH3 on the growth rate of LPVD Ge films is attributed to the photolytic production of hydrogen atoms which efficiently decompose GeH4 by hydrogen abstraction collisions.

Atomic Layer Deposition of TiN below 600 K Using N2H4

2018 ◽  
Vol 282 ◽  
pp. 232-237
Author(s):  
Adam Hinckley ◽  
Anthony Muscat
Keyword(s):  
Growth Rate ◽  
Atomic Layer Deposition ◽  
Titanium Nitride ◽  
Photoelectron Spectroscopy ◽  
Film Growth ◽  
Detection Limits ◽  
Atomic Layer ◽  
Volatile Species ◽  
X Ray ◽  
Layer Deposition

Atomic layer deposition (ALD) was used to grow titanium nitride (TiN) on SiO2with TiCl4and N2H4. X-ray photoelectron spectroscopy (XPS) and ellipsometry were used to characterize film growth. A hydrogen-terminated Si (Si-H) surface was used as a reference to understand the reaction steps on SPM cleaned SiO2. The growth rate of TiN at 573 K doubled on Si-H compared to SiO2because of the formation of Si-N bonds. When the temperature was raised to 623 K, O transferred from Ti to Si to form Si-N when exposed to N2H4. Oxygen and Ti could be removed at 623 K by TiCl4producing volatile species. The added surface reactions reduce the Cl in the film below detection limits.

Morphology of Diamond Films Produced by ECR-PACVD

1992 ◽  
Vol 280 ◽  
Author(s):  
S. Jin ◽  
T. D. Moustakas
Keyword(s):  
Growth Rate ◽  
Temperature Dependence ◽  
Hydrogen Abstraction ◽  
Diamond Films ◽  
Gas Mixtures ◽  
Cubic Crystals ◽  
Surface Morphologies ◽  
Low Pressures ◽  
Substrate Temperatures ◽  
Rate Controlling Step

ABSTRACTDiamond films were produced at a relatively low pressures (<1 Torr) by the ECR-PACVD method of gas mixtures containing CO (5%), H2 (95%) and traces of oxygen at substrate temperatures from ambient (no intentional heating) to 1050°C. Faceted surface morphologies were observed even at the lowest temperature of growth. The microstructure is dominated by octahedral crystals below 600°C, by cubic crystals at 800–900°C, and by multiply twined (111) crystals at temperatures higher than 950°C. The weak temperature dependence of the growth rate is consistent with hydrogen abstraction from the growing surface being the rate controlling step.

scholarly journals Ellipsometry and XPS comparative studies of thermal and plasma enhanced atomic layer deposited Al2O3-films

2013 ◽  
Vol 4 ◽  
pp. 732-742 ◽  
Author(s):  
Jörg Haeberle ◽  
Karsten Henkel ◽  
Hassan Gargouri ◽  
Franziska Naumann ◽  
Bernd Gruska ◽  
...  
Keyword(s):  
Growth Rate ◽  
Refractive Index ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Film Growth ◽  
Atomic Layer ◽  
Silicon Substrates ◽  
Initial State ◽  
Elemental Ratios ◽  
Layer Deposition

We report on results on the preparation of thin (<100 nm) aluminum oxide (Al2O3) films on silicon substrates using thermal atomic layer deposition (T-ALD) and plasma enhanced atomic layer deposition (PE-ALD) in the SENTECH SI ALD LL system. The T-ALD Al2O3 layers were deposited at 200 °C, for the PE-ALD films we varied the substrate temperature range between room temperature (rt) and 200 °C. We show data from spectroscopic ellipsometry (thickness, refractive index, growth rate) over 4” wafers and correlate them to X-ray photoelectron spectroscopy (XPS) results. The 200 °C T-ALD and PE-ALD processes yield films with similar refractive indices and with oxygen to aluminum elemental ratios very close to the stoichiometric value of 1.5. However, in both also fragments of the precursor are integrated into the film. The PE-ALD films show an increased growth rate and lower carbon contaminations. Reducing the deposition temperature down to rt leads to a higher content of carbon and CH-species. We also find a decrease of the refractive index and of the oxygen to aluminum elemental ratio as well as an increase of the growth rate whereas the homogeneity of the film growth is not influenced significantly. Initial state energy shifts in all PE-ALD samples are observed which we attribute to a net negative charge within the films.

scholarly journals Influence of Hydrogen-Nitrogen Hybrid Passivation on the Gate Oxide Film of n-Type 4H-SiC MOS Capacitors

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1449
Author(s):  
Yifan Jia ◽  
Shengjun Sun ◽  
Xiangtai Liu ◽  
Qin Lu ◽  
Ke Qin ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Gate Oxide ◽  
Sio2 Film ◽  
Interface Traps ◽  
Hydrogen Atoms ◽  
Mos Capacitors ◽  
Bias Stress ◽  
Current Voltage ◽  
Short Time ◽  
Secondary Ion

Hydrogen-nitrogen hybrid passivation treatment for growing high-property gate oxide films by high-temperature wet oxidation, with short-time NO POA, is proposed and demonstrated. Secondary ion mass spectroscopy (SIMS) measurements show that the proposed method causes hydrogen and appropriate nitrogen atoms to accumulate in Gaussian-like distributions near the SiO2/SiC interface. Moreover, the hydrogen atoms are also incorporated into the grown SiO2 layer, with a concentration of approximately 1 × 1019 cm−3. The conductance characteristics indicate that the induced hydrogen and nitrogen passivation atoms near the interface can effectively reduce the density of interface traps and near-interface traps. The current-voltage (I-V), X-ray photoelectron spectroscopy (XPS), and time-dependent bias stress (TDBS) with ultraviolet light (UVL) irradiation results demonstrate that the grown SiO2 film with the incorporated hydrogen passivation atoms can effectively reduce the density of oxide electron traps, leading to the barrier height being improved and the leakage current being reduced.

Chemical Vapor Deposition of Copper from an Organometallic Source

1990 ◽  
Vol 181 ◽  
Author(s):  
David B. Beach ◽  
William F. Kane ◽  
Francoise K. Legoues ◽  
Christopher J. Knors
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Film Growth ◽  
Copper Film ◽  
Chemical Vapor ◽  
Auger Spectroscopy ◽  
Copper Films ◽  
Phosphine Complexes ◽  
Transmission Electron ◽  
Substrate Temperatures

ABSTRACTHigh purity copper has been deposited from trialkyl phosphine complexes of cyclopentadienyl and methylcyclopentadienyl copper(I) by thermal chemical vapor deposition (CVD). Films as thick as 4.4 μm have been deposited at growth rates of up to 2000 Å/min with resistivites typically 2.0 μΩ cm, just slightly higher than bulk copper. Depositions were carried out at substrate temperatures between 150 and 220 °C on a variety of substrates including Si, SiO2, polyimide, and Cr/Cu. At low substrate temperatures, copper film growth appears to show some selectivity for transition metal surfaces. An activation energy of 18 kcal/mole has been measured for film growth on Cu seeded substrates. CVD copper films have been characterized by Auger spectroscopy which showed that carbon and oxygen levels are below the limits of detection. Transmission electron microscopy revealed that the copper grain size was ∼0.6μm and the grain boundaries are free of precipitates. Films show good conformality.

Epitaxial Growth of Thin Ge Films on [001] Gaas by Laser Photochemical Vapor Deposition from GeH4

1987 ◽  
Vol 101 ◽  
Author(s):  
V. Tavitian ◽  
C. J. Kiely ◽  
J. G. Eden
Keyword(s):  
Growth Rate ◽  
Film Thickness ◽  
Vapor Deposition ◽  
Epitaxial Film ◽  
Film Growth ◽  
Cross Sectional ◽  
Parallel Geometry ◽  
193 Nm ◽  
Photochemical Vapor Deposition ◽  
Substrate Temperatures

ABSTRACTEpitaxial Ge films have been grown on [001] GaAs for substrate temperatures (Ts) as low as 285°C by photodissociating GeH4 at 193 nm in parallel geometry. For a laser fluence of ~15 mJ - cm-2, the film growth rate varies from 0.6 to ~5 nm - min-1, depending upon Ts and gas pressure. Plan and cross-sectional TEM studies of the Ge/GaAs bicrystal demonstrate that the 400–700 A thick Ge films are single crystal and epitaxial with the substrate. The present limitation on epitaxial film thickness appears to be imposed by reduced adatom mobility at the temperatures investigated.

Characteristics of Polycrystalline Copper Films Made by CVD from Cu(HFA)2

1992 ◽  
Vol 260 ◽  
Author(s):  
Do-Heyoung Kim ◽  
Robert H. Wentorf ◽  
William N. Gill
Keyword(s):  
Growth Rate ◽  
Surface Roughness ◽  
Total Pressure ◽  
Deposition Time ◽  
Film Growth ◽  
Copper Films ◽  
Polycrystalline Copper ◽  
Grain Sizes ◽  
Substrate Temperatures ◽  
Deposition Conditions

ABSTRACTThin Copper films have been deposited on various substrates by the reduction of copper bis-hexafluoroacetylacetonate, Cu(HFA)2, with hydrogen to investigate the characteristics of the films made at 2–10 torr of total pressure, substrate temperatures of 280–400 °C and precursor temperatures of 55–90 °C. Under the conditions investigated, the highest growth rate was 650 Å/min. and the resistivity of the films was routinely near 2.0 μΩ-cm at 5000 Å or more thickness. Film growth rate depended on precursor concentration and substrate temperature. RBS and AES analysis indicate that the copper deposited at 310–400°C is highly pure. SEM photographs revealed that different structures form depending on substrate kind, the deposition conditions and the deposition time. The surface roughness of the films increased with increasing thickness. The reflectivity of the copper films depends on their thickness and decreases as the grain size increases. The grain sizes in the films were about 0.1–2.0 μm and are correlated with film thickness.

3-D Atomistic Kinetic Monte Carlo Simulations of Point Defect Incorporation During CVD Diamond Film Growth

1996 ◽  
Vol 441 ◽  
Author(s):  
C. Battaile ◽  
D. J. Srolovitz ◽  
J. E. Butler
Keyword(s):  
Growth Rate ◽  
Monte Carlo ◽  
Point Defect ◽  
Film Growth ◽  
Kinetic Monte Carlo ◽  
Growth Efficiency ◽  
Three Dimensions ◽  
Kinetic Monte Carlo Simulations ◽  
Cvd Growth ◽  
Substrate Temperatures

AbstractThe incorporation of vacancies and H atoms into { 100}- and { 111 }-oriented diamond films during CVD growth in an atmosphere of H, H2, CH3, and C2H2is simulated atomistically. The growing films are represented in three dimensions by a diamond cubic lattice, and the temporal evolution of the surfaces is accomplished by a kinetic Monte Carlo method. The dimer bonding of diamond atoms on the { 100} surface is treated explicitly. Growth begins on { 100}(2xl):H and { 11 }:H surfaces containing 288 and 300 atoms, respectively, in the surface plane, and the growth of approximately sixty atomic layers (18,000 atoms) is accomplished at each of fifteen substrate temperatures between 800 and 1500 K. The growth rates depend on the combined contributions to growth from CH3and C2H2, whereas the point defect concentrations depend on the ratio of C2H2to CH3growth. The maximum { 100} growth rate is achieved at approximately 1200 K. Point defect concentrations are low at temperatures below 1300 K, but become high above 1300 K. Growth efficiency, defined as the ratio of growth rate to defect concentration, is maximum for both film orientations at substrate temperatures in the vicinity of 1100 to 1200 K.

Characterization and Elimination of Forward Snapback Defects in GaAs Light Emitting Diodes

1996 ◽  
Author(s):  
J. Zimmer ◽  
D. Nielsen ◽  
T.A. Anderson ◽  
M. Schade ◽  
N. Saha ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Light Emitting Diode ◽  
Elevated Concentration ◽  
Forward Voltage ◽  
Light Emitting ◽  
Intermittent Yield ◽  
Si Doped ◽  
Secondary Ion ◽  
Furnace Pressure

Abstract The p-n junction of a GaAs light emitting diode is fabricated using liquid phase epitaxy (LPE). The junction is grown on a Si doped (~1018/cm3) GaAs substrate. Intermittent yield loss due to forward voltage snapback was observed. Historically, out of specification forward voltage (Vf) parameters have been correlated to abnormalities in the junction formation. Scanning electron (SEM) and optical microscopy of cleaved and stained samples revealed a continuous layer of material approximately 2.5 to 3.0 urn thick at the n-epi/substrate interface. Characterization of a defective wafer via secondary ion mass spectroscopy (SIMS) revealed an elevated concentration of O throughout the region containing the defect. X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) data taken from a wafer prior to growth of the epi layers did not reveal any unusual oxidation or contamination. Extensive review of the processing data suggested LPE furnace pressure was the obvious source of variability. Processing wafers through the LPE furnace with a slight positive H2 gas pressure has greatly reduced the occurrence of this defect.

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