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Simplified n-channel process achieves high performance
World Abstracts cm Microelectronics and Reliability of a number of thick film components at frequencies of 100 M H z and higher are described. Particular attention is paid to the design of inductors and the losses in such components. Two forms of thick film capacitors are described and figures for their performance given. Finally a brief discussion of frequency effects on thick film resistors is given. Evaluation methods for the examination of thick film materials. M V. COLEMAN. IERE Conf. Hybrid Microelectron. Canterbury. 221 (25 27 Sept. 1973). This paper describes the analytical and evaluation techniques developed at STL to provide a comprehensive picture of thick film materials. Examples are presented of the usefulness of the techniques in examining thick film materials and establishing the interactions which occur during processing. In particular, it is shown how the microstructure of the Du Pont 7800 and 1100 resistor systems have been identified, and how these structures are of use in understanding the electrical properties of fired resistors. Improvements of plasma spraying processes for hybrid microeleetronics. M. BRAGUIER, J. BEJAT, R. TUETA, M. VERNA, G. AUBIN and C. NATUREL. 1ERE Conf. Hybrid Mieroelectron. Canterbury. 15 (25-27 Sept. 1973). The study carried out by C.N.E.T. in connection with DESM A R Q U E S T & CEC deals with the refining of industrial plasma spraying technology with a view to sophisticated applications. Two criteria of improvement have been investigated: a higher molten particle velocity, a smaller particle size linked to a narrower grain size range. The relined technology feasibility is proved as well as its application to several kinds of deposited coatings which can be used in hybrid microelectronics. The effect of some process and material variables on the properties of thick film microwave transmission lines. K. W. WOODCOCK and P. G. BARNWELL. IERE Conf. Hybrid Mieroelectron. Canterbury. 115 (25 27 Sept. 1973). The properties of microstrip lines fabricated using thick film techniques have been studied and it is shown that they are suitable for many applications. Certain process parameters
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have been investigated with the object of optimising processing conditions. Under these conditions thick film inks can be printed having conductivities of at least 64 per cent of the bulk value and can be used for low loss lines. The importance of the substrate has also been investigated and it is shown that substrate surface fnish is not very important. Z r B z - - A ne~ thin film resistor material for hybrid microwave technology. J. Y. CALOW, K. G. KNAUFV and G. LITTEKE. IERE ConJ~ ttybrid Microelectron. Canterbury. 35 (25-27 Sept. 1973). Temperatures around 400°C are necessary for manufacturing highly reliable microwave circuits. Under these conditions the behaviour of CrNi resistors is erratic because of oxidation and phase changes. The excellent chemical and structural stability of ZrB 2 makes this material suitable as a replacement for CrNi. Principles of thick film materials tormulation. B WALTON. IERE Conj. Hybrid Microelectron. Canterbury. 39 (25 27 Sept. 1973). The composition of thick film pastes, the processes which occur during firing, and the structure of the resulting film are described and problems encountered in the development of these materials are discussed. The methods which have been used to produce conductors with high conductivity and adhesion, resistors with a wide range of value, insulants suitable for multilayer Structures, and printed capacitors with the m a x i m u m possible capacitance per unit area are outlined with emphasis on some new developments. Improved, glass-ceramic, thick film capacitors. 1. G. BOWKLEY. IERE Con.[~ ftybrid Microelectron. Canterbury. 47 (25 27 Sept. 1973i. A glass ceramic high permittivity thick film dielectric paste is described which used together with a specially developed electrode composition gives capacitors with improved mechanical and electrical properties. The fired dielectric has low porosity enabling thin layers to be used resulting in a m a x i m u m capacitance per unit area of 40,000 pF/cm 2 whilst maintaining a high breakdown voltage. The dissipation factor of the capacitors is typically 0-03 at 1 kHz with a working voltage of 50 Vd.c.
9. E L E C T R O N , I O N A N D LASER BEAMS Valorisation des technologies M O S par I'utilisation de I'implantation ionique. (Improved MOS technology using ion implantation). (in French). J. BErNArD. Eonde eleetrique 54, 15 (1974). Ion implantation, an original doping process, has come to an industrial process in the fiels of integrated circuit M O S technology. T h r o u g h some of the characteristics of this technique, different ways of overcoming the limitations of conventional MOS technologies are outlined (i.e. gatedrain capacitance, riels voltage ratio). Original applications of ion implantation are presented (P channel depletionenhancement technology, complementary on insulating substrate performance level attained. Simplified n-channel proce~ achieves high performance. R J. HUBER, K. F. SMITH, D. R. HILL, J. N. FORDEMWALT,J. W. HANSON and W. H. DOBELLE. Electronics 117 (7 March 1974). Ion-implanted metal-gate process, cheaper than silicon-gate technology, has the same advantages, operating on + 5 V for T T L compatibility; high-speed static memory has 350-ns access time and draws only 250 roW.
Techniques of laser trimming. J. WILT.KS. Electronic Components 35 (29 Jan 1974). The use of lasers is becoming more widespread tk)r resistor trimming which has in the past been a bottleneck in the production of thick film and hybrid circuits. In addition, there is an increasing range of applications for the same type of laser such as ceramic and semiconductor scribing, resistor spiralling, quartz crystal oscillator adjustment and cutting of metal foils for masks. A number of papers have been published on laser trimming and the effects on the trimmed resistors so that it might be helpful at this stage to give a back-ground to the choice of the type of laser most suited to these applications and then to outline the way in which this laser is used for resistor trimming. * Electrical activity of defects created in silicon single crystals during ion implantation. A. ANDERSSON. Electron. Electrical En~tmt 28 (61, 16 (1973). Describes measurements of the electrical behaviour of ion implanted silicon layers. The dependence of the annealing temperature (paper It and the
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have been investigated with the object of optimising processing conditions. Under these conditions thick film inks can be printed having conductivities of at least 64 per cent of the bulk value and can be used for low loss lines. The importance of the substrate has also been investigated and it is shown that substrate surface fnish is not very important. Z r B z - - A ne~ thin film resistor material for hybrid microwave technology. J. Y. CALOW, K. G. KNAUFV and G. LITTEKE. IERE ConJ~ ttybrid Microelectron. Canterbury. 35 (25-27 Sept. 1973). Temperatures around 400°C are necessary for manufacturing highly reliable microwave circuits. Under these conditions the behaviour of CrNi resistors is erratic because of oxidation and phase changes. The excellent chemical and structural stability of ZrB 2 makes this material suitable as a replacement for CrNi. Principles of thick film materials tormulation. B WALTON. IERE Conj. Hybrid Microelectron. Canterbury. 39 (25 27 Sept. 1973). The composition of thick film pastes, the processes which occur during firing, and the structure of the resulting film are described and problems encountered in the development of these materials are discussed. The methods which have been used to produce conductors with high conductivity and adhesion, resistors with a wide range of value, insulants suitable for multilayer Structures, and printed capacitors with the m a x i m u m possible capacitance per unit area are outlined with emphasis on some new developments. Improved, glass-ceramic, thick film capacitors. 1. G. BOWKLEY. IERE Con.[~ ftybrid Microelectron. Canterbury. 47 (25 27 Sept. 1973i. A glass ceramic high permittivity thick film dielectric paste is described which used together with a specially developed electrode composition gives capacitors with improved mechanical and electrical properties. The fired dielectric has low porosity enabling thin layers to be used resulting in a m a x i m u m capacitance per unit area of 40,000 pF/cm 2 whilst maintaining a high breakdown voltage. The dissipation factor of the capacitors is typically 0-03 at 1 kHz with a working voltage of 50 Vd.c.
9. E L E C T R O N , I O N A N D LASER BEAMS Valorisation des technologies M O S par I'utilisation de I'implantation ionique. (Improved MOS technology using ion implantation). (in French). J. BErNArD. Eonde eleetrique 54, 15 (1974). Ion implantation, an original doping process, has come to an industrial process in the fiels of integrated circuit M O S technology. T h r o u g h some of the characteristics of this technique, different ways of overcoming the limitations of conventional MOS technologies are outlined (i.e. gatedrain capacitance, riels voltage ratio). Original applications of ion implantation are presented (P channel depletionenhancement technology, complementary on insulating substrate performance level attained. Simplified n-channel proce~ achieves high performance. R J. HUBER, K. F. SMITH, D. R. HILL, J. N. FORDEMWALT,J. W. HANSON and W. H. DOBELLE. Electronics 117 (7 March 1974). Ion-implanted metal-gate process, cheaper than silicon-gate technology, has the same advantages, operating on + 5 V for T T L compatibility; high-speed static memory has 350-ns access time and draws only 250 roW.
Techniques of laser trimming. J. WILT.KS. Electronic Components 35 (29 Jan 1974). The use of lasers is becoming more widespread tk)r resistor trimming which has in the past been a bottleneck in the production of thick film and hybrid circuits. In addition, there is an increasing range of applications for the same type of laser such as ceramic and semiconductor scribing, resistor spiralling, quartz crystal oscillator adjustment and cutting of metal foils for masks. A number of papers have been published on laser trimming and the effects on the trimmed resistors so that it might be helpful at this stage to give a back-ground to the choice of the type of laser most suited to these applications and then to outline the way in which this laser is used for resistor trimming. * Electrical activity of defects created in silicon single crystals during ion implantation. A. ANDERSSON. Electron. Electrical En~tmt 28 (61, 16 (1973). Describes measurements of the electrical behaviour of ion implanted silicon layers. The dependence of the annealing temperature (paper It and the