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In situ cleaning of thin film metal substrates for UHV-TEM corrosion studies
Classified abstracts 61 l-61 8
these films at very high temperatures. However, critical current and field data measured at 4.2 K showed that the use of very high substrate temperatures also caused a deleterious effect on these properties. J R Gavaler et al, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (1), Jun/Feb 1973, 17-19. 30 611. Superconducting properties and structure of reactively sputtered
niobium carbide thin films. (USA) Niobium carbide thin films have been sputter deposited in a reactive argon and methane plasma at substrate temperatures of 700°C. The background pressure prior to sputtering was typically in the low 10m7 torr range, the total sputtering pressure was maintained at 2 x low3 torr and the partial pressure ratios of argon and nitrogen were monitored and controlled with a residual gas analyser. JC - H characteristics were measured by applying a pulsed field and pulsed current method and transition temperatures were determined by recording resistivity vs sample temperature. The structure was studied by x-ray diffraction. H,, is about 40 kOe and the highest Tc is 9.6 K. Several carbide phases and their mixtures were observed and have been correlated to the partial pressure ratios of the plasma. H J Spiber, Cproc 19th Nat Svmo Am Vat Sot) J Vat Sci Technol. 10 (1);Jan/Fe& 1973, 20-21. _ 30 612. In situ sputter cleaning of thin fihn metal substrates for UHV-TEM corrosion studies. (USA) A prerequisite for conducting valid corrosion experiments by in situ electron microscopy techniques is not only the achievement of UHV background pressure conditions at the site of the specimen but also the ability to clean the surface of the thin metal substrate specimen before initiation of the corrosive interaction. A miniaturized simple ion gun has been constructed for this purpose. The gun is small enough to be incorporated into an UHV electron microscope specimen chamber with hot stage in such a way as to permit bombardment of the substrate specimen while observing it by transmission electron microscopy TEM. It is shown that the ion beam generated is confined well enough to cause a sputtering removal of substrate material at a rate of approximately 5-10 A/min and to prevent the sputter deposition of contaminating material from the specimen holder. Thin single crystal Ni (100) film samples were used to demonstrate the applicability of the sputter cleaning technique, to show the removal of ion beam induced radiation damage by annealing, and to evaluate preliminary oxidation tests by selected zone dark-field microscopy. K Heinemann and H Poppa, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Tech&, 10 (l), Jan/Feb, 1973, 22-25. 30 613. Fundamentals of ion plating. (USA) The term ion plating is applied to atomistic film deposition processes in which the substrate is subjected to a flux of high energy ions sufficient to cause appreciable sputtering before and during film formation. From the standpoint of adhesion, the principal benefits obtained from ion plating are (1) ability to sputter clean the surface and maintain it ‘clean’ until the film begins to form; (2) provide a high energy flux to substrate surface giving a high surface temperature without necessitating bulk heating, thus enhancing diffusion, chemical reaction, etc; and (3) alter the surface and interfacial structure by introducing high defect concentrations, physically mixing the film and substrate material, and influencing the nucleation and growth of the depositing film. Ion plating is particularly effective in obtaining good adhesion in some systems where conventional deposition techniques give poor results. Another effect found in the ion plating process is the very great ‘throwing power’ of the depositing film material. In this paper the fundamental concepts of ion plating are reviewed along with a discussion of problems peculiar to this deposition process. Several representative applications will be described. D M Mattox, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci TechnoZ, 10 (l), Jan/Feb 1973,47-52. 30 614. Physics of ion plating and ion heam deposition. (USA) A review of some dominant mechanisms in ion plating is made. Factors influencing throwing power and film quality are discussed and the damaging effects of a high ambient gas background are considered with a view toward minimizing the harmful effects of contaminant gas background. The physical mechanisms involved in 340
an ion beam deposition process. [S Aisenberg and R Chabot, J Appl Phys, 42, 1972,2953] are examined. The effects of chamber pressure, electrical bias arrangements, and the introduction of a coevaporant source are discussed with regard to deposition rate, ultimate film quality, and throwing power of the system. S Aisenberg and R W Chabot, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (1), Jan/Feb 1973, 104-107. 30 615. Design and operation of a large scale semicontinuous electron beam evaporator. (USA) A semicontinuous electron beam evaporator has been designed and built for the application of multilayer tilms on glass substrates. The evaporator can apply three-layer coatings on substrates ten feet by twelve feet for use as high performance architectural and automotive products. Here we deal with some of the problems encountered in the design, construction, and actual operation of such a semicontinuous evaporator. Reflective glass produced in this system has become a major factor in the design of many new building projects. A D Grubb, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (l), Jan/Feb 1973, 53-57. 30 616. Thin film manufacturing by computer control. (USA) In the thin film semiconductor manufacturing field there is an ever increasing effort toward product quality and uniformity. This paper describes the computerized evaporation process for the manufacturing of interconnecting aluminium metallurgy on silicon substrates. An IBM 1800 data acquisition and control system has been programmed to interface with several modified Veeco manufacturing evaporation systems. The function of the 1800 was to completely control the evaporation cycle, record discreet and continuous process data, perform data retrieval, and provide failure recovery mechanisms. The computer-controlled runs are compared statistically to manually controlled runs in this paper for three major process parameters: film thickness, rate of deposition, and alloy concentration (copper percent concentration in the aluminium films). M S Etlion et al, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci Technol, 10 (l), Jan/Feb 1973, 80-82. 30 617. Fabrication of framed beryllium windows by high rate physical vapour deposition processes. (USA) Beryllium windows are used in radiation generators and detectors such as x-ray tubes, counters, etc, because of the low atomic number of beryllium. In current practice, thin foils of beryllium >O.OOl-in. thickness and brazed or welded into a frame which is then attached to the apparatus. This presents the problems of procurement of the thin foil and damage to it during the joining process. In our technique, beryllium is evaporated onto a substrate such as copper to the desired thickness and the window is produced by dissolving the substrate with concentrated nitric acid in the window area after masking off the area which forms the frame. Thus, a framed window of the different shapes can be produced. The principal problem is porosity in the deposit below 0.002-in. thickness. R F Bunshah and R S Juntz, (FYoc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (l), Jan/Feb 1973, 83-84. 30 618. Distribution and apparent source geometry of electron-beamheated evaporation sources. (USA) The distribution and apparent source geometry were determined for aluminium evaporation from a 12-kW 270” electron beam gun. The distribution was measured as a function of deposition rate for rates from 1000 to 50,000 A/min, 20 cm from the hearth. These measured distributions and those from other workers can be described not by a simple cosine relation, as has been assumed, but by a relation of the form (1-A) co@ 6 + A, where 0 is the angle from the vertical. The coefficient A is the normalized magnitude of an isotropic component, and n is a rate-dependent beaming exponent. The apparent source geometry was measured using a pinhole camera technique. These measurements show the evaporant to originate from the area defined by the visual beam impact point at low-to-moderate rates, and additionally from a larger virtual source at high rates or when a hearth linear is used. The run-to-run stability of the evaporant distribution was also determined. E B Graper, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci Technol, 10 (l), Jan/Feb 1973, 100-103.
these films at very high temperatures. However, critical current and field data measured at 4.2 K showed that the use of very high substrate temperatures also caused a deleterious effect on these properties. J R Gavaler et al, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (1), Jun/Feb 1973, 17-19. 30 611. Superconducting properties and structure of reactively sputtered
niobium carbide thin films. (USA) Niobium carbide thin films have been sputter deposited in a reactive argon and methane plasma at substrate temperatures of 700°C. The background pressure prior to sputtering was typically in the low 10m7 torr range, the total sputtering pressure was maintained at 2 x low3 torr and the partial pressure ratios of argon and nitrogen were monitored and controlled with a residual gas analyser. JC - H characteristics were measured by applying a pulsed field and pulsed current method and transition temperatures were determined by recording resistivity vs sample temperature. The structure was studied by x-ray diffraction. H,, is about 40 kOe and the highest Tc is 9.6 K. Several carbide phases and their mixtures were observed and have been correlated to the partial pressure ratios of the plasma. H J Spiber, Cproc 19th Nat Svmo Am Vat Sot) J Vat Sci Technol. 10 (1);Jan/Fe& 1973, 20-21. _ 30 612. In situ sputter cleaning of thin fihn metal substrates for UHV-TEM corrosion studies. (USA) A prerequisite for conducting valid corrosion experiments by in situ electron microscopy techniques is not only the achievement of UHV background pressure conditions at the site of the specimen but also the ability to clean the surface of the thin metal substrate specimen before initiation of the corrosive interaction. A miniaturized simple ion gun has been constructed for this purpose. The gun is small enough to be incorporated into an UHV electron microscope specimen chamber with hot stage in such a way as to permit bombardment of the substrate specimen while observing it by transmission electron microscopy TEM. It is shown that the ion beam generated is confined well enough to cause a sputtering removal of substrate material at a rate of approximately 5-10 A/min and to prevent the sputter deposition of contaminating material from the specimen holder. Thin single crystal Ni (100) film samples were used to demonstrate the applicability of the sputter cleaning technique, to show the removal of ion beam induced radiation damage by annealing, and to evaluate preliminary oxidation tests by selected zone dark-field microscopy. K Heinemann and H Poppa, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Tech&, 10 (l), Jan/Feb, 1973, 22-25. 30 613. Fundamentals of ion plating. (USA) The term ion plating is applied to atomistic film deposition processes in which the substrate is subjected to a flux of high energy ions sufficient to cause appreciable sputtering before and during film formation. From the standpoint of adhesion, the principal benefits obtained from ion plating are (1) ability to sputter clean the surface and maintain it ‘clean’ until the film begins to form; (2) provide a high energy flux to substrate surface giving a high surface temperature without necessitating bulk heating, thus enhancing diffusion, chemical reaction, etc; and (3) alter the surface and interfacial structure by introducing high defect concentrations, physically mixing the film and substrate material, and influencing the nucleation and growth of the depositing film. Ion plating is particularly effective in obtaining good adhesion in some systems where conventional deposition techniques give poor results. Another effect found in the ion plating process is the very great ‘throwing power’ of the depositing film material. In this paper the fundamental concepts of ion plating are reviewed along with a discussion of problems peculiar to this deposition process. Several representative applications will be described. D M Mattox, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci TechnoZ, 10 (l), Jan/Feb 1973,47-52. 30 614. Physics of ion plating and ion heam deposition. (USA) A review of some dominant mechanisms in ion plating is made. Factors influencing throwing power and film quality are discussed and the damaging effects of a high ambient gas background are considered with a view toward minimizing the harmful effects of contaminant gas background. The physical mechanisms involved in 340
an ion beam deposition process. [S Aisenberg and R Chabot, J Appl Phys, 42, 1972,2953] are examined. The effects of chamber pressure, electrical bias arrangements, and the introduction of a coevaporant source are discussed with regard to deposition rate, ultimate film quality, and throwing power of the system. S Aisenberg and R W Chabot, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (1), Jan/Feb 1973, 104-107. 30 615. Design and operation of a large scale semicontinuous electron beam evaporator. (USA) A semicontinuous electron beam evaporator has been designed and built for the application of multilayer tilms on glass substrates. The evaporator can apply three-layer coatings on substrates ten feet by twelve feet for use as high performance architectural and automotive products. Here we deal with some of the problems encountered in the design, construction, and actual operation of such a semicontinuous evaporator. Reflective glass produced in this system has become a major factor in the design of many new building projects. A D Grubb, (Proc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (l), Jan/Feb 1973, 53-57. 30 616. Thin film manufacturing by computer control. (USA) In the thin film semiconductor manufacturing field there is an ever increasing effort toward product quality and uniformity. This paper describes the computerized evaporation process for the manufacturing of interconnecting aluminium metallurgy on silicon substrates. An IBM 1800 data acquisition and control system has been programmed to interface with several modified Veeco manufacturing evaporation systems. The function of the 1800 was to completely control the evaporation cycle, record discreet and continuous process data, perform data retrieval, and provide failure recovery mechanisms. The computer-controlled runs are compared statistically to manually controlled runs in this paper for three major process parameters: film thickness, rate of deposition, and alloy concentration (copper percent concentration in the aluminium films). M S Etlion et al, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci Technol, 10 (l), Jan/Feb 1973, 80-82. 30 617. Fabrication of framed beryllium windows by high rate physical vapour deposition processes. (USA) Beryllium windows are used in radiation generators and detectors such as x-ray tubes, counters, etc, because of the low atomic number of beryllium. In current practice, thin foils of beryllium >O.OOl-in. thickness and brazed or welded into a frame which is then attached to the apparatus. This presents the problems of procurement of the thin foil and damage to it during the joining process. In our technique, beryllium is evaporated onto a substrate such as copper to the desired thickness and the window is produced by dissolving the substrate with concentrated nitric acid in the window area after masking off the area which forms the frame. Thus, a framed window of the different shapes can be produced. The principal problem is porosity in the deposit below 0.002-in. thickness. R F Bunshah and R S Juntz, (FYoc 19th Nat Symp Am Vat Sot) J Vuc Sci Technol, 10 (l), Jan/Feb 1973, 83-84. 30 618. Distribution and apparent source geometry of electron-beamheated evaporation sources. (USA) The distribution and apparent source geometry were determined for aluminium evaporation from a 12-kW 270” electron beam gun. The distribution was measured as a function of deposition rate for rates from 1000 to 50,000 A/min, 20 cm from the hearth. These measured distributions and those from other workers can be described not by a simple cosine relation, as has been assumed, but by a relation of the form (1-A) co@ 6 + A, where 0 is the angle from the vertical. The coefficient A is the normalized magnitude of an isotropic component, and n is a rate-dependent beaming exponent. The apparent source geometry was measured using a pinhole camera technique. These measurements show the evaporant to originate from the area defined by the visual beam impact point at low-to-moderate rates, and additionally from a larger virtual source at high rates or when a hearth linear is used. The run-to-run stability of the evaporant distribution was also determined. E B Graper, (Proc 19th Nat Symp Am Vat Sot) J Vat Sci Technol, 10 (l), Jan/Feb 1973, 100-103.