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Atomic layer deposition (ALD) of lanthanum oxide on glass and silicon substrates was examined using lanthanum silylamide, La[N(SiMe3)2]3, and water as precursors in the substrate temperature range of 150–250 °C. The effect of pulse times and precursor evaporation temperature on the growth rate and refractive index was investigated. The films remained amorphous regardless of the deposition conditions. The resulting La2O3films contained noticeable amounts of hydrogen and silicon and were chemically unstable while stored in ambient air. Lanthanum aluminum oxide films were achieved with stoichiometry close to that of LaAlO3at 225 °C from La[N(SiMe3)2]3, Al(CH3)3, and H2O. The lanthanum β‐diketonate precursor, La(thd)3, was used as the reference precursor.

In the period 1998-2001 the JET tokamak was operated with the MkII Gas Box divertor. On two occasions during that period a number of limiter and divertor tiles were retrieved from the torus and then examined ex situwith surface sensitive techniques. Erosion and deposition patterns were determined in order to assess the material erosion, material migration and fuel inventory on plasma facing components. Tracer techniques, e.g. injection of 13C labelled methane and tiles coated with a low-Z and high-Z marker layer, were used to enhance the volume of information on the material transport. The results show significant asymmetry in the distribution of fuel and plasma impurity species between the inner (net deposition area) and the outer (net erosion) divertor channels. No significant formation of highly hydrogenated carbon films has been found in the Gas Box structure. The important processes for material migration, and the influence of operation scenarios on the morphology of the deposits are discussed. Comparison is also made with results obtained following previous divertor campaigns.

Atomic layer deposition (ALD) was used for growing zirconium dioxide (ZrO2) thin films by alternate surface reactions between new aminoalkoxides and water. The zirconium aminoalkoxide precursors were Zr(dmae)4, Zr(dmae)2(O^tBu)2, and Zr(dmae)2(OⁱPr)2 (dmae is dimethylaminoethoxide, [OCH2CH2N(CH3)2]). Films were deposited on soda and borosilicate glass at 190−340 °C. The growth rate increased with elongated Zr precursor pulse possibly due to precursor decomposition. The as-deposited films contained substantial amounts of residual hydrogen. Reaction mechanisms were studied with a quadrupole mass spectrometer (QMS) and a quartz crystal microbalance (QCM) connected to the ALD reactor. The QMS results showed that the precursors decompose at higher temperatures, Zr(dmae)4 making an exception. According to the QCM results, all precursors start to decompose with longer Zr precursor pulses.

Amorphous PrOx based films were grown by atomic layer deposition in the temperature range 200−400 °C from Pr[N(SiMe3)2]3 and H2O on n-Si(100) and borosilicate glass substrates. The films contained considerable amounts of residual hydrogen and residual or diffused silicon. The refractive indexes of the films varied between 1.76 and 1.87. Crystallization took place after annealing at 900−1000 °C, and X-ray diffraction data indicated that the films were Pr9.33(SiO4)6O2. The effective permittivity of 70−100 nm thick films was in the range of 14−16. Annealing at 800 °C in nitrogen increased the effective permittivity to 15.6−21.0 and decreased the rechargeable trap density. Praseodymium silicate films may be applied after annealing as dielectric layers in capacitive structures.

Titanium dioxide thin films were grown by atomic layer deposition (ALD) at 200–400 °C from a new titanium precursor, titanium tetramethoxide, and water. As compared with other titanium alkoxides studied earlier, titanium methoxide shows the highest stability with respect to thermal decomposition, and can thus be used over the widest range of temperatures. The films deposited at 250 °C and above were polycrystalline with the anatase structure, whereas those deposited at 200 °C were amorphous. Except for the film deposited at 200 °C, the films contained only minor amounts of carbon and hydrogen residues. The crystalline films were shown to have photocatalytic activity in decomposing both methylene blue in aqueous solution, and solid stearic acid coated on the film surface.

HfO2films were grown by atomic layer deposition (ALD) from a new liquid precursor, Hf(ONEt2)4and H2O, at temperatures between 250 °C and 350 °C on borosilicate glass and Si(100) substrates. The highest growth rate was achieved at 300 °C, whereas the growth was essentially slower at 250 °C and ceased at 350 °C. The films possessed an O:Hf ratio of 2.15 ± 0.12, as determined by ion beam analysis. The films were weakly crystallized, showing X‐ray diffraction (XRD) peaks characteristic of monoclinic phase. The refractive index of the films varied between 1.93 and 1.96. The effective permittivities of the dielectric layers in Al/HfO2/n‐Si(100) capacitor structures were close to 10.

HfO2 films were grown by atomic layer deposition (ALD) from a new liquid precursor, Hf(ONEt2)4 and H2O, at temperatures between 250 °C and 350 °C on borosilicate glass and Si(100) substrates. The highest growth rate was achieved at 300 °C, whereas the growth was essentially slower at 250 °C and ceased at 350 °C. The films possessed an O:Hf ratio of 2.15 ± 0.12, as determined by ion beam analysis. The films were weakly crystallized, showing X-ray diffraction (XRD) peaks characteristic of monoclinic phase. The refractive index of the films varied between 1.93 and 1.96. The effective permittivities of the dielectric layers in Al/HfO2/n-Si(100) capacitor structures were close to 10.

HfO2films were grown by atomic layer deposition (ALD) from a mononuclear Hf(OtBu)2(OCMe2CH2OMe)2complex and H2O at temperatures in the range 275–400 °C on borosilicate glass and Si(100) substrates. The growth of the densest films was achieved at temperatures above 300 °C. The growth rate was influenced by the thermal decomposition of the Hf precursor. The as‐deposited films were oxides with an O:Hf ratio of 2.0 ± 0.2, although containing large amounts of impurities. Crystalline monoclinic films were grown at temperatures exceeding 325 °C, whereas at lower temperatures the films mostly remained amorphous. On the whole, the refractive index of the films varied between 1.95 and 2.00. The effective permittivities of the dielectrics in Al/HfO2/p‐Si(100) capacitor structures varied between 12 and 14, slightly increasing with growth temperature.

HfO2 films were grown by atomic layer deposition (ALD) from a mononuclear Hf(O^tBu)2(OCMe2CH2OMe)2 complex and H2O at temperatures in the range 275–400 °C on borosilicate glass and Si(100) substrates. The growth of the densest films was achieved at temperatures above 300 °C. The growth rate was influenced by the thermal decomposition of the Hf precursor. The as-deposited films were oxides with an O:Hf ratio of 2.0 ± 0.2, although containing large amounts of impurities. Crystalline monoclinic films were grown at temperatures exceeding 325 °C, whereas at lower temperatures the films mostly remained amorphous. On the whole, the refractive index of the films varied between 1.95 and 2.00. The effective permittivities of the dielectrics in Al/HfO2/p-Si(100) capacitor structures varied between 12 and 14, slightly increasing with growth temperature.

ZrO2 thin films have been deposited onto (100) silicon substrates by atomic layer deposition (ALD) using Cp2Zr(CH3)2 (Cp = cyclopentadienyl) and water as precursors at 200–500 °C. Optimal results were obtained at 350 °C, with a deposition rate of 0.43 Å (cycle)^–1. Films deposited at 300–400 °C were polycrystalline, with monoclinic ($ \bar 1 $11) as the preferred orientation. Carbon and hydrogen impurity levels in the films deposited at 350 °C were below the detection limit (0.1 at.-%) of time of flight elastic recoil detection analysis (TOF-ERDA). Dielectric properties of the deposited films were also determined. According to the high-resolution transmission electron microscope (HRTEM) analysis, 5 nm thick ZrO2 films were uniform when deposited onto untreated Si(100).

ZrO2thin films have been deposited onto (100) silicon substrates by atomic layer deposition (ALD) using Cp2Zr(CH3)2(Cp = cyclopentadienyl) and water as precursors at 200–500 °C. Optimal results were obtained at 350 °C, with a deposition rate of 0.43 Å (cycle)–1. Films deposited at 300–400 °C were polycrystalline, with monoclinic ($ \bar 1 $11) as the preferred orientation. Carbon and hydrogen impurity levels in the films deposited at 350 °C were below the detection limit (0.1 at.‐%) of time of flight elastic recoil detection analysis (TOF‐ERDA). Dielectric properties of the deposited films were also determined. According to the high‐resolution transmission electron microscope (HRTEM) analysis, 5 nm thick ZrO2films were uniform when deposited onto untreated Si(100).

Platinum thin films were grown at 300 °C by atomic layer deposition (ALD) using (methylcyclopentadienyl)trimethylplatinum (MeCpPtMe3) and oxygen as precursors. The films had excellent uniformity, low resistivity, and low-impurity contents. Structural studies by X-ray diffraction showed that the films were strongly (111) oriented. Growth rates of 0.45 Å cycle^-1 were obtained with 4 s total cycle times. The film thickness was found to linearly depend on the number of the reaction cycles. Also, the possible reaction mechanism is discussed.

HfO2 films were grown by atomic layer deposition from a mononuclear and volatile complex Hf(OCMe2CH2OMe)4 in the temperature range of 275−425 °C on borosilicate glass and Si(100) substrates. HfO2 films were formed as a result of alternate adsorption and hydrolysis steps of the hafnium precursor. The adsorption of hafnium complex was not entirely self-limiting, probably because of the thermal decomposition of the precursors. Crystalline films containing the monoclinic HfO2 phase were grown at temperatures exceeding 300−325 °C. The refractive index of the films varied between 1.8 and 2.0. The effective permittivities of the dielectrics in Al/HfO2/Si structures varied between 12 and 17.

HfO2films were produced from Hf[N(CH3)(C2H5)]4and H2O, on borosilicate glass, indium‐tin‐oxide (ITO), and Si(100) substrates, in the temperature range 150–325 °C, using atomic layer deposition (ALD). In the temperature range 200–250 °C, the growth rate of the HfO2films was 0.09 nm per cycle, but increased with both increasing and decreasing temperatures. The self‐limiting adsorption of Hf[N(CH3)(C2H5)]4at 250 °C was verified. The films were stoichiometric dioxides with an O/Hf ratio of 2.0 ± 0.1. The concentrations of residual carbon, nitrogen, and hydrogen, determined using ion beam analysis, were 0.3–0.6 at.‐%, 0.1–0.2 at.‐%, and 2–3 at.‐%, respectively. The films crystallized at growth temperatures exceeding 150–175 °C, and consisted mainly of the monoclinic HfO2phase. The refractive index of the films varied between 2.08 and 2.10. The effective permittivities of the HfO2films grown in the temperature range 200–300 °C varied between 11 and 14.

SrS and BaS thin films were grown on glass substrates using an atomic layer deposition (ALD) technique and (C5ⁱPr3H2)2Sr(THF) (1), (C5Me5)2Sr(THF)x (2), (C5Me5)2Ba(THF)x (3), and H2S as precursors. Deposition temperatures were 120−460, 155−400, and 180−400 °C with 1, 2, and 3, respectively. Growth rate of the films varied between 0.6 and 3.0 Å/cycle and all the films were polycrystalline as deposited. The amount of C, H, and O residues was found to be 0.1−0.6 at. % in the films grown at 300 °C as determined by time-of-flight elastic recoil detection analysis (TOF-ERDA). Growth mechanisms for the films grown at different temperatures were also proposed. Crystal structures of 2 and 3 were determined.

Annealing behaviour of deuterium in carbon films with different Si contents deposited by a pulsed arc discharge method in deuterium atmosphere was studied. The concentration profiles of D were measured by secondary ion mass spectrometry and elastic recoil detection techniques. A model taking into account diffusion, detrapping and trapping of D is used to describe the experimental depth profiles. Diffusion coefficients obtained for non-trapped D resulted in activation energies of 1.5 ± 0.2, 0.7 ± 0.2, 0.6 ± 0.2 and 1.2 ± 0.2 eV for samples containing 0, 6, 15 and 33 at.% of Si, respectively.

Heavy ion elastic recoil detection analysis (HI-ERDA) using 127 I ions as projectiles was applied to the compositional characterization of proton-exchanged (PE) and annealed PE waveguides in LiNbO 3 . In the measurements correlation between the simultaneously determined H and Li concentrations was obtained. In PE waveguides about 85% of Li was substituted by H. The presence of g 1 phase was determined in annealed PE waveguides through complementary X-ray diffraction measurements. From the HI-ERDA data, the stoichiometry of this phase was determined to be H 0.5 Li 0.5 NbO 3 .

Scandium oxide thin film deposition by atomic layer epitaxy was studied at 175−500 °C using Sc(thd)3 (thd = 2,2,6,6-tetramethyl-3,5-heptanedione) and (C5H5)3Sc as scandium precursors. A constant deposition rate of 0.125 Å (cycle)^-1 was observed at 335−375 °C on Si(100) and soda lime glass substrates with Sc(thd)3 and O3. The use of H2O2 as an additional oxidizer slightly increased the deposition rate to 0.14 Å (cycle)^-1. When (C5H5)3Sc and H2O were used as precursors, the growth rate of Sc2O3 was significantly higher, viz., 0.75 Å (cycle)^-1 at 250−350 °C. The effects of growth parameters such as reactant pulsing times were investigated in detail to confirm the surface-controlled growth mechanism. The crystallinity and surface morphology of the films were characterized by XRD and AFM, while ion-beam analysis (time-of-flight elastic recoil detection analysis) was used to determine the stoichiometry and impurity levels. Crystalline thin films with (111) as the dominant orientation were obtained on Si(100) when depositions were carried out at 300 °C or above from Sc(thd)3 and O3 precursors, while films deposited from (C5H5)3Sc and H2O were polycrystalline regardless of the deposition temperature. When films were deposited at 300 °C onto Si(100), the preferred orientation changed from (111) to (100) when the film thickness exceeded 200 nm. Films were stoichiometric when deposited from Sc(thd)3/O3 below 450 °C or from (C5H5)3Sc/H2O at 250 °C or above. When the films were deposited from Sc(thd)3/O3, the carbon content was below 0.1 atom % regardless of the deposition temperature, whereas the hydrogen content decreased to below 0.1 atom % when the deposition temperature was increased to 375 °C. The C and H contents of the films, deposited from (C5H5)3Sc/H2O at 300−400 °C, were around 0.1 and 0.5−0.3 atom %, respectively.

Strontium titanate thin films were grown by atomic layer deposition (ALD) at 250–325 °C from the novel strontium compound, strontium bis(tri‐isopropyl cyclopentadienyl), titanium tetraisopropoxide, and water. Though completely self‐limiting, deposition of strontium could not be achieved because of some minor decomposition of the strontium compound. This decomposition was slow enough to ensure that good control of film stoichiometry was obtained by controlling either the (Sr‐O)/(Ti‐O) pulsing ratio, or the strontium precursor exposure time. The films were polycrystalline and strongly oriented in the (100) direction. After annealing at 500 °C in air, the films with the optimal composition were found to have measured permittivity values of around 180.

Amorphous carbon nitride films have been grown by ion beam assisted deposition (IBAD) under different process conditions. The films were found to be graphitic, with π bonds between C and N atoms and a [N]/[C] ratio below 0.3. There is a relationship between the contribution of electrons from C and N atoms to the π bonds and the mechanical properties of the films. This is consistent with the arrangement of the basal planes, the softer films consisting in the pileup of weakly interacting graphitic planes and the harder films consisting in a superstructure of interconnected and corrugated basal planes. Aiming toward the synthesis of nongraphitic hard phases, we have studied the bombardment with mixtures of nitrogen/argon ions to enhance momentum transfer in the collisions. The hardest films are obtained when using a single type of ions. The hardness is reduced in the case of the N2/Ar mixture, indicating competitive mechanisms of cross-linking of basal planes.

Amorphous carbon nitride films have been grown by ion beam assisted deposition (IBAD) under different process conditions. The films were found to be graphitic, with π bonds between C and N atoms and a [N]/[C] ratio below 0.3. There is a relationship between the contribution of electrons from C and N atoms to the π bonds and the mechanical properties of the films. This is consistent with the arrangement of the basal planes, the softer films consisting in the pileup of weakly interacting graphitic planes and the harder films consisting in a superstructure of interconnected and corrugated basal planes. Aiming toward the synthesis of nongraphitic hard phases, we have studied the bombardment with mixtures of nitrogen/argon ions to enhance momentum transfer in the collisions. The hardest films are obtained when using a single type of ions. The hardness is reduced in the case of the N2/Ar mixture, indicating competitive mechanisms of cross-linking of basal planes.

Yttrium oxide thin film deposition by atomic layer epitaxy (ALE) was studied at 200–425 °C using Y(thd)3, Y(thd)3(bipyridyl), or Y(thd)3(1,10‐phenanthroline) (thd = 2,2,6,6‐tetramethyl‐3,5‐heptanedione) as an yttrium precursor, and ozone as an oxygen source. All yttrium precursors were analyzed by thermogravimetry/differential thermal analysis (TG‐DTA) and mass spectrometry (MS). Soda lime glass and Si(100) were used as substrates. With all precursors, a constant deposition rate of 0.22–0.23 Å (cycle)–1was observed at 250–350 °C on both substrates, indicating a surface‐controlled growth and similar surface species at the deposition temperatures used. The effect of growth parameters, such as reactant pulsing times, was investigated in detail at 350 °C using Y(thd)3. Deposited films were characterized by X‐ray diffraction (XRD) and atomic force microscopy (AFM) in order to determine crystallinity and surface morphology, while ion‐beam analysis and X‐ray photoelectron spectroscopy (XPS) were used to analyze stoichiometry and impurity levels. Infrared (IR) measurements were performed to determine the type of carbon impurity. Crystalline films with a (400) dominant orientation were obtained when depositions were carried out within the ALE window (temperature range of 250–375 °C), but films deposited below 250 °C were nearly amorphous. Preferential orientation changed from (400) to (222) when deposition temperatures were raised slightly above the ALE window to 375 °C, where a partial decomposition of Y(thd)3probably takes place. Judging from the impurity levels of the films and growth rates, the adducting of Y(thd)3does not bring about any advantages in the ALE growth of Y2O3.

TiO2thin films have been grown on amorphous soda lime glass and polycrystalline silicon substrates from TiI4and H2O2by atomic layer deposition (ALD) in the temperature range 250–490 °C. The film growth rate and refractive index increased linearly with growth temperature up to 300 °C. Between 300 °C and 400 °C, the film growth rate tended to stabilize. Above 400 °C, there was a further rapid increase in the growth rate, together with a corresponding increase in the thickness profile. The refractive index reached 2.70–2.75 in the films grown above 300 °C. The films contained low amounts of residual hydrogen and were virtually iodine‐free. When deposited below 300 °C and above 325 °C, the films contained weakly crystallized, but still distinct, anatase and rutile phases, respectively. Reflective high‐energy electron diffraction (RHEED) studies revealed that the uppermost layers of the films grown on silicon at 275 °C, 325 °C, and 425 °C contained anatase phase, regardless of deposition temperature. In the temperature range 300–325 °C, a transition region was established where either the films became less ordered, or they contained rather strongly ordered, but unstable, suboxide phases. The suboxide phase, when present, was transformed into a mixture of anatase and rutile when stored in air at room temperature.

A self-starting stretched-pulse mode-locked erbium-doped fiber laser that uses fast and slow semiconductor saturable absorbers is described. By using two absorbers, we obtained reliable operation at a fundamental repetition rate with 250??pJ of pulse energy without multiple-pulse breakup. External chirp compensation was used to compress the highly chirped pulses to durations of 135??fs.