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Testing and reliability of throughplatings in thin-film hybrid-circuits
1046
World Abstracts on Microelectronics and Reliability
X-ray and microscopic investigations of resistors containing CdO and RuO_,. RADOMIR KUZEL, JOSEF BROUKAL and DOBROSLAV KINDL. IEEE Trans. Components Hybrids Mr9 Technol. CHMT-4(3), 245 (1981). X-ray diffraction analysis was used to determine the crystalline phases of cadmium and ruthenium present after processing thick film resistors formulated from CdO, RuO 2, and cadmium-leadbarium borate glass. On firing a phase with diffraction pattern characteristic of the pyrochlore-structure type is formed through reaction of RuO2 and the modifying ions present in the glass. The observed cubic lattice parameter a o corresponds closely to that reported for Pb_,Ru20 6. The observed decrease in RuO 2 correlated well with variations in resistance associated with changes in the firing temperature. It was observed that increased CdO content resulted in deterioration of the stability of the thick film resistors formed. Scanning electron microscopy showed that resistors high in CdO showed a higher concentration of voids than those formed from composites conta!ning 70-80 percent glass.
New mounting technologies in the manufacture of hybrid circuits. E. HEYMANN. Nachrichtemechnik Elektronik 31 (8), 335 (1981), (in German). Hybrid circuits with an increased number of highly integrated monolithic circuits will codetermine the future device generation of telecommunication. In order to increase the yield in the manufacture of hybrid circuits and in order to meet the reliability requirements, suitable mounting technologies for the placing of ic chips in film circuits were developed of recent years. Besides the widely spread chip-and-wire method with automatic wire bonds further methods such as the use of flat packs, chip, carrier or the film bonding have been developed.
Silver migration in thick film conductors and chip attachment resins. M. V. COLEMANand A. E. WINSTER. Microelectronics J. 12 (4), 23 (1981). The rates of silver migration of silver alloy tfiick film conductors and silver-loaded resins have been examined under conditions of 98 % relative humidity at 25°C and 85 % relative humidity at 85°C, and various d.c. power loadings. The value of a current limiting resistor in series with the sample under test was shown to have a considerable effect on migration. The presence of debris in the gap between conductor tracks and on the substrate
surface was shown to increase the rates of migration. The nature and composition of the substrate surface also affected the migration ofconductors printed and fired under identical conditions. Overglazes over conductors and cross-over dielectrics between conductors slowed moisture penetration to the conductor surfaces but did not prevent dendritic growth from occurring. Migration always occurred from the cathode to the anode but it was necessary for silver ions to move from the anode to the cathode to provide the dendrite source material. It was concluded that care was necessary in interpreting data from silver migration tests but all silver loaded materials will migrate in the presence of moisture, and the only sure solution would be improved encapsulation or dry atmosphere sealing.
Computer-assisted development of hybrid integrated hyperfrequency circuits. W. SENF and C. WEANER. Nachrichtentechnik Elektronik 31 (81, 318 (1981), (in German). The small computer programmes HASE 1-4 and the large computer programmes HANSA I and II for the analysis of four- or eight-pole networks of the superfrequency technique are represented. Their application is illustrated by a microstrip filter and by transistor amplifiers. Transistor parameters are determined with the programme TRANS. M K 13 is a data correction programme.
Testing and reliability of throughplatings in thin-film hybridcircuits. H. G. KADEREn', D. KOCH and A. SCHLEMM. Feinwerktechnik Messtechnik 89 (5), 209 (1981), (in German). Throughplatings in thin-film hybrid circuits are electrically conducting connections between the wiring planes on the front and back side through the chip. During the production of the thin-film hybrid circuits with fault-free throughplatings, certain unit-specific conditions have to be fulfilled and a meticulous process run must be guaranteed. With the process development and quality assurance for the production of thin-film hybrid circuits, a testing method has been developed during which the resistance of the throughplating is exactly determined as quality characteristic thereof. This testing method and the testing appliance are described, and the results on reliability tests with throughplatings are given.
9. ELECTRON, ION AND LASER BEAM TECHNIQUES The contiguous disk technology for high density bubble memories. H. JouvE and J. MAGNIN. Microelectronics J. 12 (5), 8 (1981). A new generation of magnetic bubble memory devices using "contiguous disk" elements as propagation patterns is under development in various laboratories. The propagation patterns are delineated by ion implantation in the top layer of the bubble garnet material. The magnetic domains are displaced by the charged walls created around the disks under the influence of an in-plane field. The shape of these contiguous elements allows a tenfold increase in storage density when compared to the conventional asymmetric permalloy chevrons. The operation of the different elementary functions necessary for a working chip is
described, as well as the technological process necessary for its fabrication. The possible chip architectures are reviewed with their respective performances.
Review of ion-implanted bubble devices. P. I. BONYHARD. MicroelectronicsJ. 12 (5), 5 (198l). This review is intended to assist with the assessment of the ion-implanted bubble technology. Attention is focused on product-oriented device work. A more complete understanding of the background of this technology may, however, be gained from the papers that are listed as references and from the papers referenced therein.
World Abstracts on Microelectronics and Reliability
X-ray and microscopic investigations of resistors containing CdO and RuO_,. RADOMIR KUZEL, JOSEF BROUKAL and DOBROSLAV KINDL. IEEE Trans. Components Hybrids Mr9 Technol. CHMT-4(3), 245 (1981). X-ray diffraction analysis was used to determine the crystalline phases of cadmium and ruthenium present after processing thick film resistors formulated from CdO, RuO 2, and cadmium-leadbarium borate glass. On firing a phase with diffraction pattern characteristic of the pyrochlore-structure type is formed through reaction of RuO2 and the modifying ions present in the glass. The observed cubic lattice parameter a o corresponds closely to that reported for Pb_,Ru20 6. The observed decrease in RuO 2 correlated well with variations in resistance associated with changes in the firing temperature. It was observed that increased CdO content resulted in deterioration of the stability of the thick film resistors formed. Scanning electron microscopy showed that resistors high in CdO showed a higher concentration of voids than those formed from composites conta!ning 70-80 percent glass.
New mounting technologies in the manufacture of hybrid circuits. E. HEYMANN. Nachrichtemechnik Elektronik 31 (8), 335 (1981), (in German). Hybrid circuits with an increased number of highly integrated monolithic circuits will codetermine the future device generation of telecommunication. In order to increase the yield in the manufacture of hybrid circuits and in order to meet the reliability requirements, suitable mounting technologies for the placing of ic chips in film circuits were developed of recent years. Besides the widely spread chip-and-wire method with automatic wire bonds further methods such as the use of flat packs, chip, carrier or the film bonding have been developed.
Silver migration in thick film conductors and chip attachment resins. M. V. COLEMANand A. E. WINSTER. Microelectronics J. 12 (4), 23 (1981). The rates of silver migration of silver alloy tfiick film conductors and silver-loaded resins have been examined under conditions of 98 % relative humidity at 25°C and 85 % relative humidity at 85°C, and various d.c. power loadings. The value of a current limiting resistor in series with the sample under test was shown to have a considerable effect on migration. The presence of debris in the gap between conductor tracks and on the substrate
surface was shown to increase the rates of migration. The nature and composition of the substrate surface also affected the migration ofconductors printed and fired under identical conditions. Overglazes over conductors and cross-over dielectrics between conductors slowed moisture penetration to the conductor surfaces but did not prevent dendritic growth from occurring. Migration always occurred from the cathode to the anode but it was necessary for silver ions to move from the anode to the cathode to provide the dendrite source material. It was concluded that care was necessary in interpreting data from silver migration tests but all silver loaded materials will migrate in the presence of moisture, and the only sure solution would be improved encapsulation or dry atmosphere sealing.
Computer-assisted development of hybrid integrated hyperfrequency circuits. W. SENF and C. WEANER. Nachrichtentechnik Elektronik 31 (81, 318 (1981), (in German). The small computer programmes HASE 1-4 and the large computer programmes HANSA I and II for the analysis of four- or eight-pole networks of the superfrequency technique are represented. Their application is illustrated by a microstrip filter and by transistor amplifiers. Transistor parameters are determined with the programme TRANS. M K 13 is a data correction programme.
Testing and reliability of throughplatings in thin-film hybridcircuits. H. G. KADEREn', D. KOCH and A. SCHLEMM. Feinwerktechnik Messtechnik 89 (5), 209 (1981), (in German). Throughplatings in thin-film hybrid circuits are electrically conducting connections between the wiring planes on the front and back side through the chip. During the production of the thin-film hybrid circuits with fault-free throughplatings, certain unit-specific conditions have to be fulfilled and a meticulous process run must be guaranteed. With the process development and quality assurance for the production of thin-film hybrid circuits, a testing method has been developed during which the resistance of the throughplating is exactly determined as quality characteristic thereof. This testing method and the testing appliance are described, and the results on reliability tests with throughplatings are given.
9. ELECTRON, ION AND LASER BEAM TECHNIQUES The contiguous disk technology for high density bubble memories. H. JouvE and J. MAGNIN. Microelectronics J. 12 (5), 8 (1981). A new generation of magnetic bubble memory devices using "contiguous disk" elements as propagation patterns is under development in various laboratories. The propagation patterns are delineated by ion implantation in the top layer of the bubble garnet material. The magnetic domains are displaced by the charged walls created around the disks under the influence of an in-plane field. The shape of these contiguous elements allows a tenfold increase in storage density when compared to the conventional asymmetric permalloy chevrons. The operation of the different elementary functions necessary for a working chip is
described, as well as the technological process necessary for its fabrication. The possible chip architectures are reviewed with their respective performances.
Review of ion-implanted bubble devices. P. I. BONYHARD. MicroelectronicsJ. 12 (5), 5 (198l). This review is intended to assist with the assessment of the ion-implanted bubble technology. Attention is focused on product-oriented device work. A more complete understanding of the background of this technology may, however, be gained from the papers that are listed as references and from the papers referenced therein.