- Email: [email protected]
RC-active filters in single-layer tantalum RC-film technology
428
World Abstracts on Microelectronics and Reliability
AI films was measured and compared with the resistivity calculated in terms of the function which takes into account both the external and the internal size effects. A comparison of the theoretical and experimental curves shows that the specular reflection coefficient (p) is small, while the coefficient of electron transmission through the grain boundary (r) increases with increasing film thickness. Electrical properties of RF sputtering systems. J. H. KELLER and W. B. PENNEBAKER.I B M J. Res. Dev. 23, (1) 3 (January 1979). A theory is developed that gives a relatively complete electrical characterization of rf sputtering systems. Three types of systems are analyzed: tuned substrate, driven substrate, and controlled area ratio of electrode (CARE) systems. The theory is applicable to any of these systems that do not use magnetic fields to confine the plasma. Given the input rf power and voltage at the target, and any other parameters that can be specified as independent variables (e.g., pressure, substrate drive voltage, tuning impedance, and system geometry), the theory provides explicit values for all dc and rf electrical parameters of the system. The dc bias developed at the substrate is explained and related to the resputtering energy. In addition, an approximate calculation is presented for the ion density in the plasma; this calculation allows a semiquantitative estimate of the rf voltage developed at the target for a given value of rf input power. It also shows the influence of pressure and frequency on rf sputtering system operation. Comparisons are made with real rf sputtering systems; these show that the theory is quite successful in predicting the operation of these systems. In addition, a much better understanding is achieved of some of the complex electrical phenomena encountered in these systems. The theory should prove useful both for new system design and for diagnostic work on existing equipment. Analog ICs divide accurately to conquer computation problems. Yu JEN WONG. Electronics p. 120 (12 April 1979). Housed in dual in-line packages, the hybrids can multiply, divide, or take the square root. A new analytical expression for the T.C.R. of thin monocrystalline metal films. C. R. TELLIER. Electrocomp. Sci. Technol. 5, 209 (1979). The analysis of electrical conductivity of continuous thin monocrystalline metal film has been treated by assuming that the scattering from other sources than grain-boundaries can be described by an effective relaxation time. This relaxation time method is applied to the temperature coefficient of resistivity and leads to an analytical approximate equation in terms of the grainboundary reflection coefficient r and the reduced thickness k. Comparison of the results with those deduced from the exact equation (derived from the Mayadas and Shatzkes theory) shows that they deviate by less than 5°,, in large k-, p-, and r-ranges. RC-active filters in single-layer tantalum RC-film technology. HANS-WERNER RENZ, HOLM BAEGER, ERNST LUEDER, HANS-JUERGEN TILCH and TRAUGOTT KALLFASS. Proc. IEEE 67, (1) 37 (January 1979). A new composition of reactively sputtered Ta-oxinitride is used as a basic material for thin-film resistors as well as for thin-film capacitors; this single-layer technique enables an economic fabrication process for integrated RC circuits with lumped or distributed RC components. A bandpass circuit with lumped components for a dialing tone receiver and a voiceband low pass with distributed elements for PCM channel filtering are described; in either case a very small size allowed a complete filter to be packed in regular DIL-packages, and good performance and stability were obtained. Problems in the production and measurement of very high vacuum, especially in applications, and a new approach to
measurement based on the use of field emission. L. DE CHERNATONY and J. YARWOOD. Vacuum 29, (3) 125. Opinions are expressed about the needs in the development of vacuum systems in which a very high vacuum is to be created. Topics considered are sealing materials, new pumps, especially for an oil-free vacuum environment, a new type of gauge based on field electron emission able to indicate surface gas coverage as well as extend downwards the partial pressure range of a mass spectrometer and the further automation of industrial vacuum plant in which repetitive processes are undertaken. Miniaturized thick-film RC-active filters for PCM application. KEIJ1 SUZUKI and YUKIO KATSUTA. Proc. IEEE 67, (1) 34 (January 1979). This paper presents thick-film RC-active filters developed for use in pulse-code modulation (PCM) systems. Filters for PCM telephone transmission systems are required to be small in size and low cost in production, and they must have good performance. The filters presented have a twelve-lead single in-line package configuration. Dimensions are 5-ram thick, 10-mm high, and 30-mm wide. They meet the D3-Channel Bank requirements. The transmitting filter is a seventh-order bandpass filter (BPF). The receiving filter is a fifth-order low-pass filter (LPF) with an input RC stage which acts as a lossy sample and hold circuit. To achieve miniaturization, thick-film resistors are printed on one side of alumina substrate. On the other side, one chip of quad op-amps and monolithic ceramic-chip capacitors are assembled. Considering economical production, these filters are designed with the following features : (1) only one type of equal-valued capacitors is used; (2) to get good yields, a multiple-feedback configuration having low sensitivity to circuit elements is adopted ; (3) a fast deterministic trimming method is used with computer-controlled laser-trim equipment. Multiple insulator layers on GaAs studied by Auger analysis. J. T. GRANT, H. L. HARTNAGEL, F. L. SCHUERMEYER, B. BAYRAKTAROGLU and D. MAYS. Int. J. Electron. 46, (2) 209 (1979). Recently research was focused on the formation of multiple layer anodic insulators on GaAs to obtain superior passivation layers. In particular A1203 films in conjunction with native oxide films were evaluated. In this paper Auger analysis studies are reported on Al203-native oxide films on GaAs. The results indicate that oxygen migrates during anodization towards the interface while Ga and As migrate towards the surface. Sputtering process model of deposition rate. J. H. KELLER and R. G. SIMMONS. IBM J. Res. 23, (1) 24 (January 1979). A model of the sputtering process has been developed that predicts the deposition rate of a sputtering system with parallel-plate geometry. By using data for sputtering yield vs voltage obtained from an ion-beam sputtering system, the model applies a new theory for computing the backscatter material, and, from the results, predicts deposition rates. The model also considers the effects of charge exchange in the sheaths, and of re-emission of sputtered material at the substrate. The model is valid for magnetic, tuned substrate, driven substrate, and controlled area ratio diode systems. Comparison with observed deposition rates shows good agreement for clean systems. An experimental APL program that uses the model has been written. Trimming of thin and thick film resistors. J. P. LE PENDEVEN. Acta Electronica 21, (4) 319 (1978). (In French.) In this article devoted to the trimming of resistors in hybrid microelectronics the accent is placed on the practical aspect of the use of lasers. The article is broken down into
World Abstracts on Microelectronics and Reliability
AI films was measured and compared with the resistivity calculated in terms of the function which takes into account both the external and the internal size effects. A comparison of the theoretical and experimental curves shows that the specular reflection coefficient (p) is small, while the coefficient of electron transmission through the grain boundary (r) increases with increasing film thickness. Electrical properties of RF sputtering systems. J. H. KELLER and W. B. PENNEBAKER.I B M J. Res. Dev. 23, (1) 3 (January 1979). A theory is developed that gives a relatively complete electrical characterization of rf sputtering systems. Three types of systems are analyzed: tuned substrate, driven substrate, and controlled area ratio of electrode (CARE) systems. The theory is applicable to any of these systems that do not use magnetic fields to confine the plasma. Given the input rf power and voltage at the target, and any other parameters that can be specified as independent variables (e.g., pressure, substrate drive voltage, tuning impedance, and system geometry), the theory provides explicit values for all dc and rf electrical parameters of the system. The dc bias developed at the substrate is explained and related to the resputtering energy. In addition, an approximate calculation is presented for the ion density in the plasma; this calculation allows a semiquantitative estimate of the rf voltage developed at the target for a given value of rf input power. It also shows the influence of pressure and frequency on rf sputtering system operation. Comparisons are made with real rf sputtering systems; these show that the theory is quite successful in predicting the operation of these systems. In addition, a much better understanding is achieved of some of the complex electrical phenomena encountered in these systems. The theory should prove useful both for new system design and for diagnostic work on existing equipment. Analog ICs divide accurately to conquer computation problems. Yu JEN WONG. Electronics p. 120 (12 April 1979). Housed in dual in-line packages, the hybrids can multiply, divide, or take the square root. A new analytical expression for the T.C.R. of thin monocrystalline metal films. C. R. TELLIER. Electrocomp. Sci. Technol. 5, 209 (1979). The analysis of electrical conductivity of continuous thin monocrystalline metal film has been treated by assuming that the scattering from other sources than grain-boundaries can be described by an effective relaxation time. This relaxation time method is applied to the temperature coefficient of resistivity and leads to an analytical approximate equation in terms of the grainboundary reflection coefficient r and the reduced thickness k. Comparison of the results with those deduced from the exact equation (derived from the Mayadas and Shatzkes theory) shows that they deviate by less than 5°,, in large k-, p-, and r-ranges. RC-active filters in single-layer tantalum RC-film technology. HANS-WERNER RENZ, HOLM BAEGER, ERNST LUEDER, HANS-JUERGEN TILCH and TRAUGOTT KALLFASS. Proc. IEEE 67, (1) 37 (January 1979). A new composition of reactively sputtered Ta-oxinitride is used as a basic material for thin-film resistors as well as for thin-film capacitors; this single-layer technique enables an economic fabrication process for integrated RC circuits with lumped or distributed RC components. A bandpass circuit with lumped components for a dialing tone receiver and a voiceband low pass with distributed elements for PCM channel filtering are described; in either case a very small size allowed a complete filter to be packed in regular DIL-packages, and good performance and stability were obtained. Problems in the production and measurement of very high vacuum, especially in applications, and a new approach to
measurement based on the use of field emission. L. DE CHERNATONY and J. YARWOOD. Vacuum 29, (3) 125. Opinions are expressed about the needs in the development of vacuum systems in which a very high vacuum is to be created. Topics considered are sealing materials, new pumps, especially for an oil-free vacuum environment, a new type of gauge based on field electron emission able to indicate surface gas coverage as well as extend downwards the partial pressure range of a mass spectrometer and the further automation of industrial vacuum plant in which repetitive processes are undertaken. Miniaturized thick-film RC-active filters for PCM application. KEIJ1 SUZUKI and YUKIO KATSUTA. Proc. IEEE 67, (1) 34 (January 1979). This paper presents thick-film RC-active filters developed for use in pulse-code modulation (PCM) systems. Filters for PCM telephone transmission systems are required to be small in size and low cost in production, and they must have good performance. The filters presented have a twelve-lead single in-line package configuration. Dimensions are 5-ram thick, 10-mm high, and 30-mm wide. They meet the D3-Channel Bank requirements. The transmitting filter is a seventh-order bandpass filter (BPF). The receiving filter is a fifth-order low-pass filter (LPF) with an input RC stage which acts as a lossy sample and hold circuit. To achieve miniaturization, thick-film resistors are printed on one side of alumina substrate. On the other side, one chip of quad op-amps and monolithic ceramic-chip capacitors are assembled. Considering economical production, these filters are designed with the following features : (1) only one type of equal-valued capacitors is used; (2) to get good yields, a multiple-feedback configuration having low sensitivity to circuit elements is adopted ; (3) a fast deterministic trimming method is used with computer-controlled laser-trim equipment. Multiple insulator layers on GaAs studied by Auger analysis. J. T. GRANT, H. L. HARTNAGEL, F. L. SCHUERMEYER, B. BAYRAKTAROGLU and D. MAYS. Int. J. Electron. 46, (2) 209 (1979). Recently research was focused on the formation of multiple layer anodic insulators on GaAs to obtain superior passivation layers. In particular A1203 films in conjunction with native oxide films were evaluated. In this paper Auger analysis studies are reported on Al203-native oxide films on GaAs. The results indicate that oxygen migrates during anodization towards the interface while Ga and As migrate towards the surface. Sputtering process model of deposition rate. J. H. KELLER and R. G. SIMMONS. IBM J. Res. 23, (1) 24 (January 1979). A model of the sputtering process has been developed that predicts the deposition rate of a sputtering system with parallel-plate geometry. By using data for sputtering yield vs voltage obtained from an ion-beam sputtering system, the model applies a new theory for computing the backscatter material, and, from the results, predicts deposition rates. The model also considers the effects of charge exchange in the sheaths, and of re-emission of sputtered material at the substrate. The model is valid for magnetic, tuned substrate, driven substrate, and controlled area ratio diode systems. Comparison with observed deposition rates shows good agreement for clean systems. An experimental APL program that uses the model has been written. Trimming of thin and thick film resistors. J. P. LE PENDEVEN. Acta Electronica 21, (4) 319 (1978). (In French.) In this article devoted to the trimming of resistors in hybrid microelectronics the accent is placed on the practical aspect of the use of lasers. The article is broken down into