Pulsed CVD Research Articles

Effect of the Thickness and the Annealing Conditions of the Catalytic Ni Films on the Graphene Films Grown by a Rapid-Thermal Pulse CVD

Effect of the Thickness and the Annealing Conditions of the Catalytic Ni Films on the Graphene Films Grown by a Rapid-Thermal Pulse CVD

564 パルス化直流プラズマCVD法によるTiO_2からのTiN成膜(OS8-3 軽量化,機能化のための表面創製技術,OS8 軽量化,機能化のための界面・表面創製ならびに塑性加工技術)

564 パルス化直流プラズマCVD法によるTiO_2からのTiN成膜(OS8-3 軽量化,機能化のための表面創製技術,OS8 軽量化,機能化のための界面・表面創製ならびに塑性加工技術)

563 パルス化直流プラズマCVD法によるB_2O_3からのcBN薄膜の作成と評価(OS8-3 軽量化,機能化のための表面創製技術,OS8 軽量化,機能化のための界面・表面創製ならびに塑性加工技術)

563 パルス化直流プラズマCVD法によるB_2O_3からのcBN薄膜の作成と評価(OS8-3 軽量化,機能化のための表面創製技術,OS8 軽量化,機能化のための界面・表面創製ならびに塑性加工技術)

Pulsed Supermagnetron Plasma CVD of a-CN<sub>x</sub>:H Electron-Transport Films for Au/a-CN<sub>x</sub>:H/p-Si Photovoltaic Cells

Hydrogenated amorphous carbon nitride (a-CNx:H) films were formed on p-Si wafers set on a lower elec-trode by pulsed supermagnetron plasma CVD using i-C4H10 and N2 gases. Lower electrode RF power (LORF) of 13.56 MHz (50 - 800 W) was modulated by a 2.5-kHz pulse at a duty ratio of 12.5%, and upper electrode RF power (UPRF) of 50 - 400 W was supplied continuously. The optical band gap decreased with an increase in LORF at each UPRF. The open circuit voltage of Au/a-CNx:H/p-Si photovoltaic cells (a-CNx:H film thickness: 25 nm) was about 200 mV for each cell, and the short circuit current density and energy conversion efficiency increased with LORF for each UPRF. The highest energy conversion efficiency of 0.81% was obtained at UPRF/LORF of 200/800 W.

Direct Synthesis of TiN and BN Films from TiO<sub>2</sub> and B<sub>2</sub>O<sub>3</sub> by Using Pulsed DC Plasma CVD Method

Direct Synthesis of TiN and BN Films from TiO<sub>2</sub> and B<sub>2</sub>O<sub>3</sub> by Using Pulsed DC Plasma CVD Method

Low-temperature pulsed CVD of thin layers of metallic ruthenium for microelectronics and nanoelectronics. Part 3: Nucleation phenomena during the growth of ruthenium layers

The data on the peculiarities of nucleation and initial stages of the growth of ruthenium layers on different surfaces in the temperature range 110–350°C under the pulsed deposition from the vapor phase with the participation of the carbonyl-diene precursor Ru(CO)3C6H8, as well as NH3, N2O, and H2 as the second reagent are generalized.

Highly Conducting, Transparent Rhombic/Cubic Indium Tin Oxide Nanocomposite Thin Films

Polycrystalline tin-doped indium oxide (ITO) films were deposited at growth rates up to 0.8 nm/s on glass using pulsed nebulization CVD. The precursor solutions were nebulized into droplets with a modal size significantly smaller than predicted by theory. Rhombohedral distortion of the structure was observed in a number of films leading to nanocomposites of the rhombic/cubic structures. The rhombic phase is rarely observed without applying high pressure. The average mobility (carrier concentration) for the partially rhombic films was 27 cm2/(V s) (5.7 × 1020 per cm3), whereas for the purely cubic films it was 11 cm2/(V s) (4.0 × 1020 per cm3). These values are higher than for sputtered films. The significantly improved mobility is explained by lower strain/disorder in the presence of the rhombic phase. The higher carrier concentration may relate to increased tin solubility in rhombohedral phase. Median film optical transparency was 89%, and the median rms roughness value was 6 nm, comparable to sputtered films.

Low-temperature pulsed CVD of ruthenium thin films for micro- and nanoelectronic applications, Part 1: Equipment and methodology

An overview is presented of the low-temperature pulsed CVD equipment and techniques used in these experiments for making ruthenium thin films with Ru(CO)3(C6H8) as the first precursor and NH3, H2, or N2O as the second precursor.

Preparation of Iridium Thin Film by Pulse CVD from Ir(acac)(CO)2

Iridium thin films were deposited by pulse CVD with using dicarbonyl(acetylacetonato)iridium Ir(acac)(CO)2 as a precursor. Precursor was characterized by DTA and mass spectrometry; effusion Knudsen method was used for determination of thermodynamic parameters of sublimation process. By means of high temperature mass spectrometry precursor vapor decomposition was studied in vacuum, oxygen and hydrogen. Analysis of gaseous by-product composition has shown that the main products of reaction are acetylacetone, СО, СО2 and С2Н3О of presumably radical character. Mechanism of thermal transformations of precursor molecules at interaction with surface was supposed. Ir films deposited at substrate temperature between 240 and 300{degree sign}C were characterized by XPS and AFM. Ir in the films is in metal and chemically associated states, size of Ir particles is 4-20 nm.

Deposition of Ir Nanostructured Thin Films by Pulse CVD

Nanostructured thin iridium films were deposited by pulse CVD. Tris(acetylacetonato)iridium(III) was used as the precursor. The thermochemical properties of this precursor were determined by mass spectrometric monitoring its vapour phase interaction with heated surfaces both in vacuum and in atmospheres of H2 and О2. The results obtained provided a guide for understanding which pulse CVD process conditions to use for growing thin films of iridium using hydrogen or oxygen as gas reactant. Deposited iridium film thicknesses were varied from 5 to 25 nm. Iridium films were characterized by means of SEM, AFM, HRTEM and XPS.

Pulse CVD Deposition of Ru Films from Ru(II) ή3-Allylic Complex

A ruthenium(II) ή3-allylic complex Ru(nbd)(allyl)2 (nbd = norbornadiene) was used as precursor for pulse CVD thin Ru films on silicon substrates. Preliminary study of thermal behavior of precursor was carried out: temperature dependence of vapor pressure was measured by means of Knudsen method with mass spectrometric analysis of gas phase composition; thermodynamic parameters of sublimation process were calculated. By means of high temperature mass spectrometry in situ the process of vapor thermo destruction was investigated in vacuum: vapor decomposition starts at relatively low temperature (about 180оC); the major gas by-products are the radicals of ligands - allyl, norbornadiene and their combinations. Deposition of Ru films was carried out in vacuum and hydrogen. XPS, AFM and HREM study have shown metal state of Ru in films. In the presence of hydrogen the film consists of Ru particles with size of 3.5 nm. Sample surface is smooth; mean square roughness is 0.17 nm.

Deposition of Ir Nanostructured Thin Films by Pulse CVD

not Available.

Preparation of Iridium Thin Film by Pulse CVD from Ir(acac)(CO)2

not Available.

Structural study of device quality silicon germanium thin films deposited by pulsed RF plasma CVD

Microstructures in silicon germanium thin films deposited by pulsed rf plasma CVD have been studied with the help of small-angle X-ray scattering (SAXS) and high-resolution transmission electron microscopy (HRTEM). With lowering of the pulse duty cycle the size of the particles incorporated in the films from the plasma decreases. However, the particles become more symmetric in shape and crystalline in nature. At 75% duty cycle the films have the highest photosensitivity. The increase in SAXS scattering at 75% has been explained by the formation of uniform-size nanocrystallites of SiGe. Urbach energy variation with the duty cycle also suggests the formation of nanocrystallites.

157 パルス化直流プラズマCVD装置によって成膜されたDLC膜の密着性向上(OS3-2最先端金型技術2)

157 パルス化直流プラズマCVD装置によって成膜されたDLC膜の密着性向上(OS3-2最先端金型技術2)

Deposition of DLC film from adamantane by using pulsed discharge plasma CVD

Diamond like carbon films are deposited on silicon and quartz substrates using adamantane as a sole source of carbon by pulsed discharge plasma chemical vapor deposition. Tauc band gap of such films has been successfully tuned from 1.7eV to 2.9eV. Iodine incorporation is observed to favor the growth of such films and induces disorder in the films. It also brings down in energy the on-set of photon absorption. Such iodine incorporated diamond like carbon films may be interesting candidates for the new coming applications such as for heterojunction photovoltaic devices.

Ultra-Thin Ruthenium Films by Pulsed Chemical Vapor Deposition

Ruthenium films have been deposited via a pulsed CVD process using tris(2,2,6,6-tetramethyl-3,5-heptanedionato) ruthenium (i.e., Ru(thd)3) , oxygen, and hydrogen at 280 and 300{degree sign}C. Film resistivity near theoretical values (16 μΩ-cm at 3 nm) was achieved with repeatability. Films were smooth and continuous down to 2 nm; a low density of pinholes could be observed on films with 1 nm thickness. Adhesive tape tests indicated good adhesion. Carbon content is low.

Synthesis of SBA-15/carbon composite with an ink-bottle-like pore structure by a novel pulse CVD technique

A novel and easy post modification method, pulse chemical vapor deposition (pulse CVD), was developed to tailor the pore-opening of SBA-15 while largely keeping its surface area and pore volume. By using acetylene as carbon precursor and nitrogen as carrier gas, the pore-mouth of SBA-15 was effectively reduced from 8.1 nm to 5.1 nm within 5 min while maintaining the pore body at 8.1 nm. This ink-bottle-structured SBA-15/carbon composite only losses 12% BET specific surface area and 16% total pore volume, respectively. The SBA-15/carbon composite is highly hexagonally ordered and has similar particle morphology as the original SBA-15. The effect of three pore modification factors—the number of cycles of pulse CVD, the ratio of acetylene/nitrogen and the feeding time of carbon precursor, on the final pore structure of the SBA-15/carbon composite is also studied.

Batch ALD: Characteristics, comparison with single wafer ALD, and examples

A comparison is made between single-wafer and (vertical) batch systems for Atomic Layer Deposition (ALD). Various characteristic times that play a role in such systems are compared. Many of these characteristic times are substantially shorter in single wafer systems. In case wafers with a high density of deep trenches are processed in a batch system, the required length of the precursor pulse could be as long as 10–60 s, depending on the specific chemistry of the process. This time is largely determined by the time it takes to saturate the very large surface of the trenched substrates. Despite that, batch systems with load sizes of 50–100 wafers are superior in terms of overall throughput. Two classes of ALD processes are distinguished, ‘normal’ ALD, in which the active precursors are separated by inert gas purges, and partial ALD in which one of the ALD steps is replaced by a pulsed CVD step. In the first category two examples are discussed, Al 2O 3 and HfO 2 ALD, characterized by short and long surface saturation times, respectively. In the second category (partial) ALD of TiN and Si 3N 4 are discussed. First a thin TiN layer is deposited through a short CVD pulse; in the second, true ALD pulse NH 3 reacts with the TiN surface to remove any remaining Cl. It is demonstrated that this procedure combines a high overall growth rate with a low sheet resistance. In the Si 3N 4 process the first pulse is a CVD process in which a thin layer of amorphous Si is deposited. In the second (ALD) pulse N and/or NH2 radicals generated by a remote plasma are used to convert the Si into Si 3N 4. The paper concludes with a short discussion on new types of carbide and nitride films that have potential to be deposited in batch type ALD systems.

ナノパルスプラズマの状態評価及びDLC膜合成への応用

The nanopulse CVD method open the way of DLC deposition at sub-atmospheric pressure. On the other hand, plasma characteristics of nanopulse plasma have not investigated yet. In this paper, we have investigated the plasma characteristics of nanopulse plasma using the Langmuir probe method at low pressure. Using of the characteristics of high electron density created by positive pulse, we have developed the bipolar nanopulse generator consisted with Static Induction Thyristor devices. The deposition rate of this bipolar nanopulse plasma CVD method is five fold higher than that of normal unipolar pulse CVD method. The productivity of plasma assisted coating will be significantly improved by this bipolar nanopulse CVD method.