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Optical properties of inhomogeneous films
Classified
abstracts
266-273
A wedge-shaped device is described which uses gravity to give positive mask-substrate contact. The technique prevents “oversized” thin films and ensures temperature equality. J S Lemke and R P Swifka, Rev Sci Instrum, 35 (II), 1964, 16041605. 26 : 22 266. Transistorized emission regulator for ion gauge and RF mass spectrometer tubes. (USA) An emission stabilizer for Bayard-Alpert ionization gauges or mass spectrometers is described. A drift of less than 0.08 per cent over 2.5 hours can be assured, whilst a change of input supply voltage from 105 to 125 V caused a change of the order of only 10 per cent. N C Petersen and I W Price, Rev Sci Instrum, 35 (2), 1964, 16201621. 27. Leak detectors and leak detection 27 : 22 267. New mass spectrometer leak detector. (USSR) The new detector has a twin rotor mechanical vacuum pump and an iridium alloy cathode. This enables the svstem to be evacuated directly, starting from atmospheric pressure.A vacuum of 2-5 lO-4 torr is reached in less than 10 min, without the use of liquid nitrogen. The detector is designed for use with either helium or hydrogen as test gas. Its sensitivity is 1-5 x 10m6 microlitres/sec with the former and 5 x lo-* microlitres/sec with the latter. Sensitivity calibration is carried out with the help of a calibrated diffusion type leak. The transition from one gas to the other is achieved by changing the accelerating voltage from 400 V (helium) to 800 V (hydrogen). A general view of the instrument together with the twin rotor pump and the helium calibrating leak is given. The dependence of sensitivity on gas pressure in the spectrometer is (USSR) shown on a curve. L E Levina et al, Pribory i Tekh Eksper, (5), 1964, 157-161 (in Russian).
28. Heating
(in Russian). 30 271. Investigation (USSR)
equipment
and thermometers
28 :41 268. The heating in vacuum of silicon substrates to temperatures
greater than 800°C. (USA) An electron gun installation is described capable of heating silicon substrates to temperatures in excess of 1200°C. The bombardment method is considered preferable to conventional heating systems. (USA) J Wales and A J Teal, JSci Inst, 41 (8)) 1964,521. 28 : 30 : 42 269. The deposition of alumina, silica and magnesia films by electron bombardment evaporation. (Great Britain) Evaporated alumina films had the highest resistance and stability. The silica films, when dry, had the lowest tan 6 value but capacitance, leakage resistance and dielectric loss were erratic unless full hermetic sealing was applied. Evaporated magnesia film had the lowest breakdown voltage and poor leakage characteristics. B Lewis, Microelectronics & Reliab, 3 (2). 1964,109-120. 29. Miscellaneous 29 Application of rhenium and its alloys in electro-vacuum instruments. See abstract number 303.
III. Vacuum 30. Evaporation
applications and sputtering
30 Application of ellipsometry to the study of phenomena on surfaces prepared in high vacuum. See abstract number 244. 30 Optical coefficients of thin Cr films obtained by thermal evaporation in vacuum. See abstract number 250. 30 Optical properties of inhomogeneous films. See abstract number 252. 162
30 Optical study of thin absorbing films on a metal surface. See abstract number 253. 30 Synthesis of multilayer coatings. See abstract number 254. 30 Determination of thickness and refractive index of thin films as an approach to the study of biological macro molecules. See abstract number 255. 30 Increased scope of ellipsometric studies of surface film formation. See abstract number 257. 30 Computational techniques for the use of the exact Drude equation in reflection problems. See abstract number 258. 30 Thin film X-ray standard. See abstract number 259. 30 Vertically positioned substrate holder. See abstract number 265. 30 The deposition of alumina, silica and magnesia films by electron bombardment evaporation. See abstract number 269. 30:41 270. Investigation of oxidation and evaporation of resistance alloys in vacuum. (USSR) A series of Cr-Ni alloys were examined as regards high temperature performance in air at various pressures. Low pressure tests proved the more onerous since the protective oxide layer is reduced and evaporation favoured. Nickel chromium alloy X20H80 had a satisfactory lifein a vacuum of lo-” torr at a temperature up to 1200°C. (USSR) S G Murovannaia and E N Marmer, Elektro-Termiia, 39 (5)) 1964
of the Bi-0
: 33 : 41
system by electron diffraction.
The BiO films were prepared by two methods. In the first, powdered BiO was sublimated in vacuum of 5 x 1O-5 torr on to an NaCl facet at temperature ranging from room to 350°C. Depending on substrate temperature and rate of evaporation, the character of the deposit varied. At very low rates of sublimation, the deposit was polycrystalline at all substrate temperatures. High rates of sublimation produced predominantly pointed or oblique deposits depending on whether the substrate was hot or cold. Usually both types are intermingled. In the second method of preparation, pure metallic bismuth was sublimated at 5 x 10m5 torr on to the NaCl and the resultant film oxidised slowly by heating to 450°C for several hours. With this method the oxide film had a pointed or oblique structure, depending on whether the original metal film had a mosaic or oriented structure. The electron diffraction patterns showed the existence of a tetragonalphase oxide of composition B&O,.,-,.,. (USSR) A A Zavialova et al, Crystallography, 9 (6). 1964, 857-863 (in Russian). 30 : 33 272. Dispersion and anisotropy in normal single axis films. (USSR)
Permalloy films approx 400 A thick were vacuum deposited at the rate of 150 Aimin on clean glass substrates at 5 x 1O-5 torr and room temperature. The distribution of the anisotropy field HK and the direction of easy and difficult magnetization were investigated by magneto-optical methods. HK depends on the angle of incidence of the molecular beam on the substrate by a relation of the form HK = a tan*/3 I_ A. The average direction of easy magnetization follows that given by the Hauss distribution function. Although the angle of dispersion of HK in the films is about IO”, the value of Hc/HK as well as the shape of the hysteresis loop show that the films were of the monocrystalline (single axis) type. (USSR) (Hc = coercive force). R V Telesnin et al, Phys of Metals & Met Sri, 18 (5)) 1964,691-696 (in Russian) 30.41 273. Use of the phenomenon of positive surface ionization in the study of the cathodic sputtering of metals. ( USSR) One of the fundamental problems in connection with sputter in-
vestigations is the need of obtaining monochromatic ion beams of different intensities and striking the surface at a definite angle. The
abstracts
266-273
A wedge-shaped device is described which uses gravity to give positive mask-substrate contact. The technique prevents “oversized” thin films and ensures temperature equality. J S Lemke and R P Swifka, Rev Sci Instrum, 35 (II), 1964, 16041605. 26 : 22 266. Transistorized emission regulator for ion gauge and RF mass spectrometer tubes. (USA) An emission stabilizer for Bayard-Alpert ionization gauges or mass spectrometers is described. A drift of less than 0.08 per cent over 2.5 hours can be assured, whilst a change of input supply voltage from 105 to 125 V caused a change of the order of only 10 per cent. N C Petersen and I W Price, Rev Sci Instrum, 35 (2), 1964, 16201621. 27. Leak detectors and leak detection 27 : 22 267. New mass spectrometer leak detector. (USSR) The new detector has a twin rotor mechanical vacuum pump and an iridium alloy cathode. This enables the svstem to be evacuated directly, starting from atmospheric pressure.A vacuum of 2-5 lO-4 torr is reached in less than 10 min, without the use of liquid nitrogen. The detector is designed for use with either helium or hydrogen as test gas. Its sensitivity is 1-5 x 10m6 microlitres/sec with the former and 5 x lo-* microlitres/sec with the latter. Sensitivity calibration is carried out with the help of a calibrated diffusion type leak. The transition from one gas to the other is achieved by changing the accelerating voltage from 400 V (helium) to 800 V (hydrogen). A general view of the instrument together with the twin rotor pump and the helium calibrating leak is given. The dependence of sensitivity on gas pressure in the spectrometer is (USSR) shown on a curve. L E Levina et al, Pribory i Tekh Eksper, (5), 1964, 157-161 (in Russian).
28. Heating
(in Russian). 30 271. Investigation (USSR)
equipment
and thermometers
28 :41 268. The heating in vacuum of silicon substrates to temperatures
greater than 800°C. (USA) An electron gun installation is described capable of heating silicon substrates to temperatures in excess of 1200°C. The bombardment method is considered preferable to conventional heating systems. (USA) J Wales and A J Teal, JSci Inst, 41 (8)) 1964,521. 28 : 30 : 42 269. The deposition of alumina, silica and magnesia films by electron bombardment evaporation. (Great Britain) Evaporated alumina films had the highest resistance and stability. The silica films, when dry, had the lowest tan 6 value but capacitance, leakage resistance and dielectric loss were erratic unless full hermetic sealing was applied. Evaporated magnesia film had the lowest breakdown voltage and poor leakage characteristics. B Lewis, Microelectronics & Reliab, 3 (2). 1964,109-120. 29. Miscellaneous 29 Application of rhenium and its alloys in electro-vacuum instruments. See abstract number 303.
III. Vacuum 30. Evaporation
applications and sputtering
30 Application of ellipsometry to the study of phenomena on surfaces prepared in high vacuum. See abstract number 244. 30 Optical coefficients of thin Cr films obtained by thermal evaporation in vacuum. See abstract number 250. 30 Optical properties of inhomogeneous films. See abstract number 252. 162
30 Optical study of thin absorbing films on a metal surface. See abstract number 253. 30 Synthesis of multilayer coatings. See abstract number 254. 30 Determination of thickness and refractive index of thin films as an approach to the study of biological macro molecules. See abstract number 255. 30 Increased scope of ellipsometric studies of surface film formation. See abstract number 257. 30 Computational techniques for the use of the exact Drude equation in reflection problems. See abstract number 258. 30 Thin film X-ray standard. See abstract number 259. 30 Vertically positioned substrate holder. See abstract number 265. 30 The deposition of alumina, silica and magnesia films by electron bombardment evaporation. See abstract number 269. 30:41 270. Investigation of oxidation and evaporation of resistance alloys in vacuum. (USSR) A series of Cr-Ni alloys were examined as regards high temperature performance in air at various pressures. Low pressure tests proved the more onerous since the protective oxide layer is reduced and evaporation favoured. Nickel chromium alloy X20H80 had a satisfactory lifein a vacuum of lo-” torr at a temperature up to 1200°C. (USSR) S G Murovannaia and E N Marmer, Elektro-Termiia, 39 (5)) 1964
of the Bi-0
: 33 : 41
system by electron diffraction.
The BiO films were prepared by two methods. In the first, powdered BiO was sublimated in vacuum of 5 x 1O-5 torr on to an NaCl facet at temperature ranging from room to 350°C. Depending on substrate temperature and rate of evaporation, the character of the deposit varied. At very low rates of sublimation, the deposit was polycrystalline at all substrate temperatures. High rates of sublimation produced predominantly pointed or oblique deposits depending on whether the substrate was hot or cold. Usually both types are intermingled. In the second method of preparation, pure metallic bismuth was sublimated at 5 x 10m5 torr on to the NaCl and the resultant film oxidised slowly by heating to 450°C for several hours. With this method the oxide film had a pointed or oblique structure, depending on whether the original metal film had a mosaic or oriented structure. The electron diffraction patterns showed the existence of a tetragonalphase oxide of composition B&O,.,-,.,. (USSR) A A Zavialova et al, Crystallography, 9 (6). 1964, 857-863 (in Russian). 30 : 33 272. Dispersion and anisotropy in normal single axis films. (USSR)
Permalloy films approx 400 A thick were vacuum deposited at the rate of 150 Aimin on clean glass substrates at 5 x 1O-5 torr and room temperature. The distribution of the anisotropy field HK and the direction of easy and difficult magnetization were investigated by magneto-optical methods. HK depends on the angle of incidence of the molecular beam on the substrate by a relation of the form HK = a tan*/3 I_ A. The average direction of easy magnetization follows that given by the Hauss distribution function. Although the angle of dispersion of HK in the films is about IO”, the value of Hc/HK as well as the shape of the hysteresis loop show that the films were of the monocrystalline (single axis) type. (USSR) (Hc = coercive force). R V Telesnin et al, Phys of Metals & Met Sri, 18 (5)) 1964,691-696 (in Russian) 30.41 273. Use of the phenomenon of positive surface ionization in the study of the cathodic sputtering of metals. ( USSR) One of the fundamental problems in connection with sputter in-
vestigations is the need of obtaining monochromatic ion beams of different intensities and striking the surface at a definite angle. The