velocity H’ impact. The dilTerence is explained and a simple procedure suggested to relate energy spectra for the two isotopes. J E Harriss et al, J Appl Phys, 51 (IO). 1980. 53445350.
37 4640. Energy-selective SESD imaging utilizing a CMA. (USA) A particularly simple conversion of a scanning Auger system for ESD ion energy distributions and scanning ESD has been developed. This approach combines the advantages of the small spot-size electron guns and mapping systems developed for SAM with the capability of ESD for the detection of hydrogen. Our intended use for the device is detection and mapping of surface concentrations of hydrogen on metals. The characteristics of SESD are illustrated with the preliminary results of an investigation into the ESD properties of hydrogenic adsorbates on Nb. It is shown that the ESDIED exhibit distinct differences indicative of the surface preparation, and that the ESD ion angular distributions have an eNect on the observed contrast relationships in SESD. L A Larson et al, J Vat Sci Techuol, 17 (6). 1980, 1364-1366. 37 4641. The Si(lll)-Pd interface: spectroscopic evidence of chemical processes at liquid nitrogen temperature. (USA) We present the results of angle integrated photoelectron spectroscopy (hv=21.2 eV) on Si(lll)-Pd interfaces. We have found that some intermixing between Si and Pd takes place also when the interface is prepared at liquid nitrogen temperature (LNT). After preparation at LNT the intermixing increases at room temperature (RT). The results are discussed in connection with the interface formation mechanism. (Italy) I Abbati et al. J Vat Sci Technol, 17 (6). 1980. 1303-1305. 37 4642. X-ray photoelectron spectroscopy study of the surface adsorption of lead naphthenate. (USA) The adsorption of lead naphthenate on the surfaces of metals, oxides and sulphides was studied by means of X-ray photoelectron spectroscopy (XPS). Lead naphthenate physically adsorbs on all surfaces. It chemisorbs on surfaces with basic sites, such as oxides, sulphides and metals treated in basic solutions before adsorption. The IWO states have distinct XPS spectra: the Pb(4/, 2) binding energy for the physically adsorbed state is 139. I eV, whereas that for the chemisorbed state is 136.6 eV. Conditions of surface preparation that result in the formation ofeach state are described. P A Bertrand and P D Fleischauer, J Vat Sci Technol. 17 (6). 1980. 130%1314. 37 4643. Phosphorus concentration in hydrogenated amorphous silicon using ion-implanted references. (USA) The phosphorus content in glow-discharge deposited hydrogenated amorphous silicon film has been determined using Auger electron spectroscopy. Precision low concentration phosphorus ion-implants into hydrogenated amorphous silicon were used as standards to accurately determine the sensitivity factor for phosphorus in hydrogenated amorphous silicon. J H Thomas 111, J Vat Sci Technol, 17 (6). 1980, 13061308. 37 4644. Mass spectrometric studies of material evolution from magnetic liquid seals. (USA) Evolution of ferrotluid contained in two vacuum rotary feedthroughs is studied for the first time by a time-of-Right mass spectrometer in order to provide information on the background material these seals introduce into a high vacuum system. The seals used diester and poly(phenyl ether) based ferrofluids. The rate ofevolution of the diester was found to be of the order of 3 x lo-” g s-’ and that of the poly(phenyl ether) was below the detection limit of the mass spectrometer, i.e. IO-” g s-‘. The oxygen and water evolution, which are generally of prime interest in vacuum application, were found to be 10e9 g SK’ for both seals at 3000 rpm. The feedthroughs were successfully employed in precision abrasion mass spectrometric experiments. K Raj and M A Grayson, Ret) Sci Insrrum. 51 (IO), 1980, 1370-1373. 3-l 4645. A simple method of end-point determination for plasma etching. (USA) In this paper it is shown that end-points detected by using a commercial vacuum from a plasma reactor. (Switzerland) M L Hitchman and V Eichenberger, 1378-1379.
37 4646. A versatile spectrometer system for scanning Auger microscopy. (GB) An electron spectrometer system is described with some illustrative spectra. The system combines the requirements of scanning Auger microscopy with those of high resolution spectroscopy. The spectrometer is a concentric hemispherical analyser with a four-element input lens and can be operated with a high signal sensitivity, low energy resolution (Ca 7eV window), with 0.1 sr angle or with a high resolution and reduced sensitivity. R Browning, J Phys E: Sci fnsrrum, 14 (1). 1981, 58-61. 37 4647. Emission spectroscopy of glow-discharge and sputtering plasmas used in amorphous Si:H film deposition. (USA) We analyse the optical emission spectra of flow discharge (gd) plasmas and find evidence for Si-H complexes. From a similar analysis of sputtering plasmas, we find that a significant silicon-hydrogen gas phase reaction does nor occur. The dissimilarities of the plasmas out of which gd and sputtered films are condensed coupled with the similarities of the films themselves, lead us to reason that the properties of amorphous Si: H films are determined by structure that is locked into the growing film surfaces. To study the physics of how the hydrogen enters the Si: H matrix, one must turn to-investigations of these &fac&. M A Paesler et al, .I Vat Sci Tech&, 17 (6). 1980. 1322-1325. 37 4648. On surface coatings and secondary yield of Nb,Sn and Nb. (USA) In rfcavities, Nb,Sn and Nb surfaces show features that have been blamed on unavoidable oxide layers. In addition to the oxidation. physiand chemisorption take place, which strongly influence the work function and the secondary yield. To measure quantitatively the oxide and sorption layers, X-ray photoelectron spectroscopy (XPS) measurements have been carried out for Nb surfaces subjected to the typical procedures, such as oxipolishing (OP), ultra-high vacuum annealing (HT), handling in Lacuum’, air, H,O, H,O*, CH,OH or impact of ions and electrons. The XPS results show that all Nb,Sn and Nb surfaces used are coated with a dielectric oxide layer thicker than 2 nm, saturating in growth at 6 nm. These oxides are coated with a sorption layer containing 0 and C of at least 2 monolayer equivalent (ML), but as much as IO ML has been observed. The excited states of the oxides and the excited localized states of the Nb,Os-H,O chemisorption state enhance the secondary electron emission, whereas the physisorbed hydrocarbons show enhanced absorption of slow electrons, especially after electron or X-ray induced ‘conditioning’. The enhanced secondary emission from the Nb,Os-H,O state positively charges the dielectric, lowering the work function, whereas the enhanced electron absorption of ‘conditioned’ hydrocarbons negatively charges this region and increases the work function. (Germany) M Crunder and J Halbritter, J Appl Phys, 51 (IO). 1980, 53965412. 37 4649. An inexpensive digital crystal thickness monitor. (GB) A simple digital type quartz crystal thickness monitor with high sensitivity and good resolution has been designed and fabricated. In the same design another method using the phase-locked loop technique has been provided for the measurement of thickness of the films which can be compared with the value obtained by the digital frequency counter. Both these methods can simultaneously be used for the accurate measurement of the rate of deposition and the total thickness of the films. (India) A Balasubramanian et al, J Phys E: Sci Instrum, I4 (I), 1981, 123-126.
IV. Materials technology 42. GLASS, ELASTOMERS, PAINTS AND
CERAMICS, WAXES, OILS
PLASTICS, LACQUERS, 42
in plasma etching gauge to monitor J
can be readily the effluent gas 17 (6).
4650. Vacuum applications of metal foams. (USA) One new material with considerable potential for vacuum metal foam. This paper presents a variety of applications copper may be used in vacuum. B R F Kendall, J Vat Sci Technol, 17 (6). 1980, 1385.
application in which