ISSN:0022-5355    

DOI:10.1116/1.1318024

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

ISSN:0022-5355    

DOI:10.1116/1.1318027

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

Low resistivity aluminum films have been deposited by dc bias sputtering without excessive presputtering. Minimum resistivity occurs for a bias(VB)of approximately −40 V and, in contrast to the case for sputtered molybdenum, the resistivity increases for higher negative biases. For as-deposited 6500-Å films, resistance ratios (R.T./4.2 K) greater than 20 were obtained forVB=−40 V, indicating a minimum resistivity within 5% of bulk. Total (tensile) stress for these same films (deposited at substrate temperatures of 120–200 C) is∼+1.5×109 dyn/cm2forVB=−40 V, dropping to∼+0.8×109 dyn/cm2forVB=−125to −150 V. The films exhibit an increasingly rougher surface for increasing negative bias, in contrast with sputtered molybdenum films, which show the opposite bias dependence.

ISSN:0022-5355    

DOI:10.1116/1.1318029

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

Effects of substrate temperature on the resistivity and TCR of Ta thin film resistors have been studied by depositing films onto glass substrates for which the temperature at the start of sputtering was varied from 25 to 285 °C. For these films which were reactively sputtered in oxygen flowing at a constant rate, the film resistivity decreases, the film TCR increases in the positive direction, and the average oxygen concentration in the films decreases as the initial substrate temperature is increased. The fact that the dependence of the resistivity and TCR of these films on the average oxygen concentration is the same as for films in which the oxygen concentration is varied by depositing the films at a single substrate temperature and varying the oxygen flow rate into the system indicates that the main effect of substrate temperature during deposition is to change the oxygen concentration in the films, rather than directly introducing any temperature-dependent changes in the film properties. For films containing from 10–20 at.% oxygen, the Ta condensation coefficient and film growth rate are largely independent of temperature.

ISSN:0022-5355    

DOI:10.1116/1.1318030

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

A rotary drum evaporator has proved itself capable of depositing thin chromium films that are comparable if not superior to films deposited by other techniques. The thickness of the films is uniform and pinholes have been reduced to less than five per square inch. The model described is capable of handling 12 glass substrates of different sizes, but the design can easily be scaled up to accommodate even more.

ISSN:0022-5355    

DOI:10.1116/1.1318031

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

An effusive molecular beam, a copper target, and several quartz crystal microbalances were used to measure the spatial distributions of reflected and sublimatedCO2andH2Omolecules. These spatial distributions were found to be identical for surface temperatures ranging from 55 to 210 K forCO2and from 55 to 160 K forH2O, and for gas temperatures below 300 K. Experimental results agreed with the diffuse cosine law spatial distribution within the accuracy of the measurement.

ISSN:0022-5355    

DOI:10.1116/1.1318032

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

CaF2films, 30–1000 Å in average thickness, were formed at 25–380 °C on {001} NaCl under ultrahigh vacuum conditions. Transmission electron diffraction and microscopy showed that these films consisted of many {110} oriented crystallites coexisting with {001} oriented crystallites. It was found that high intensity 50-, 80-, and 100-kV electron beams in the electron microscope altered the structure of these films. The electron beams had a randomizing effect on theCaF2films. Extra diffraction rings were observed that could not be explained in terms ofCaF2or double diffraction reflections. These extra rings were due to CaO. No diffraction evidence for free Ca metal was obtained. Previous work by Evans suggested thatCaF2decomposes to form free Ca under the action of an electron beam. In the present work it is believed that electron irradiation first produces free Ca metal which then oxidizes to CaO in the relatively high oxygen partial pressure in the electron microscope.

ISSN:0022-5355    

DOI:10.1116/1.1318033

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

In discontinuous films the difference between the electrostatic energy of a charge at rest on an island and a charge which has just been placed on an island by tunneling must be accounted for in a phenomonological explanation of the conduction mechanism. This energy difference can exceed the static electrostatic energy which is normally assumed to give rise to the thermally activated resistance experimentally observed in such films. It is also shown that the initial charge creation in discontinuous films may be more likely to arise from carrier injection at the electrodes than from island ionization in the middle of the film because of a lowered energy barrier height and an enhanced electric field in the vicinity of the electrodes. Under suitable conditions electrode injection will show a barrier energy lowering proportional to the square root of the applied field as is experimentally observed. Experimental results which may be indicative of electrode injection are presented.

ISSN:0022-5355    

DOI:10.1116/1.1318034

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

摘要:

Studies have been made of the scattering and deexcitation of thermal energy beams of metastable Ar, He, Ne, andN2from an oxygen-covered germanium surface. It has been found that the survival of incident metastable species after a surface collision is strongly dependent on the degree of surface gas coverage. Using the metastable time-of-flight technique, both angular scattering and time-of-flight distributions were measured for the scattered metastable species. Changes in the TOF distribution of the scattered molecules relative to the incident distribution have been observed. In addition, changes in angular distribution as well as total metastable survival have been observed as a function of incident angle. Differences in survival for the various species studied have been measured and are discussed in terms of the excitation energy of the excited electron in the metastable atom relative to unfilled energy states at the germanium surface.

ISSN:0022-5355    

DOI:10.1116/1.1318035

出版商:American Vacuum Society    

年代:1973

数据来源: AIP

ISSN:0022-5355    

DOI:10.1116/1.1318037

出版商:American Vacuum Society    

年代:1973

数据来源: AIP