- Email: [email protected]
Reliability of hybrid microcircuits in use today
144
WORLD
ABSTRACTS
ON MICROELECTRONICS
offer more protection from mechanical abrasions and foreign materials. Some electrical parameters of transistors as well as integrated circuits were measured before and after paesivation; no significant differences were f o u n d ~ l o degradation on these parameters was found after a*|000-hr operating life test on pasaivated and non-passiv#ted units. R e l i a b i l i t y Q hybrid m i ~ t s i n use today. R. J. STaAtm, Proc. 1970 20th Electronic Component: Conf., Washington, 13-15 May (1970), p. 16. Results of testing nearly 125,000 hybrid microcircuits from eight manufacturers show the need for formal testing and screening to avoid potential quality and reliability problems. The units were tested by AC Electronics from 1967 to late 1969. The resultant data was gathered and analyzed as part of an Air Force study contract. Information presented in this paper includes the test procedures imposed on the microcircuit suppliers before shipment, as well as those performed after delivery at AC Electronics. Test data are summarized relative to receiving-inspection, sample inspection and environmental testing, extended performance testing and subsequent assembly and field performance. The continued need for new evaluation techniques is further evidenced by results of stepped stress mechanical and environmental testing, performed per MIL-STD-883 under the referenced Air Force study contract on three different hybrid circuits from three manufacturers. The observed on-aircraft failure rate of hybrid microcircuits subjected to this controlled processing and testing through November 1969 was 0-465 failures per 1,000,000 hr. This failure rate has a 90 per cent confidence interval of 0.218 to 0-874 failures per 1,000,000 hr. It pertains to 3, C I R C U I T A N D S Y S T E M S R ] ~ J A B I I A ~ , P o w e r s y s t e m reliability evaluation. R. BILLINTON, Int. y. Engng F_,Juc. 8 (1970), p. 467. Quan6tative reliability evaluation is becoming increasingly important in the economic appraisal of alternate engineering facilities. Reliability has often been expressed in qualitative terms which do not readily lend themselves to system optimization, particularly where digital computers are utilized. A graduate course on reliability engineering of one term's duration was introduced in the Electrical Engineering Department at the University of Saskatchewan in 1965. This course has proved quite successful and has been attended by approximately equal numbers of graduate students from the Mechanical and Electrical Departments. Some of this material has also been briefly introduced into an undergraduate course taken by electrical engineering students. In 1967 a one-term graduate course entitled "Power System Reliability" was introduced into the graduate program. This course supplements the existing graduate classes presently given in the power systems area. Compare
reliability at a glance.
C. H. K A ~ ,
Electron. Des. 18, September (1970), p. 69. System
AND RELIABILITY
hybrid microcircuits used on aircraft and a missile. These circuits were exposed to mechanical shock, vibration, temperature cycling, and all of the other environments present outside of the pressurized, temperaturecontrolled cabin of the vehicle.
Tramdent a, m e a l i n g of d e f e c t s i n i r r a d i a t e d silicon d e v i c e s . B. L. GI~GORY and H. H. S A N ~ , Proc.
IEEE$8, No. 9, September (1970), p. 1328. The annealing of radiation-produced defects in semiconductor devices is discussed briefly for e°Co gamma-ray and 1-MeV clectron damage, and in detail for fast-neutron damage. The effects on the re-ordering processes of varying the material parameters and the irradiation conditions are considered. Transient annealing of neutron damage near room temperature has been investigated for a wide variety of devices, and the data are presented in generalized form to increase their usefulne~ to device and circuit designers. Based on the experimental results, physical models are suggested for the re-ordering processes which occur during the annealing of neutron damage. Electron density is shown to be the most important factor governing the rate of transient annealing. Annealing factors are estimated for very early times (1 ~ ) following neutron exposure. Suggestions are made to minimize the effects of transient annealing on devices. ReliabiliW testing. R. G. RAUTH et al., Eva. Engng 8, No. 5, September-October (1969), pp. 14, 15. RCA's approach to the IC specification in action helping to produce more reliable products is described. The four reliability screening levels based on Mil-Std-883 are given. MAINTENANCE
AND RF~UNDANCY
reliability can be improved by using redundant components, and its numerical value can be calculated by using the binomial expansion. However, the analytic approach can be tedious. A set of computer-generated curves that makes system reliability comparisons possible at a glance is given. The curves can be applied to two types of redundancy calculation: back-up and back-off. Back-up redundancy means that incremental or fractional spares are available to replace failed units in order to maintain a given capability. Back-off redundancy refers to the probability of meeting a degraded requirement--something less than a desired goal. L o w - c o s t v i d e o distribution a m p l i f i e r g i v e s inc r e a s e d reliabili W. G. A. STeve~, E/e~tron. Engng, October (1970), p. 47. Design details are given for a video distribution amplifier which can be used in any required mode, and in the simplest possible manner. Constructional requirements are outlined and an indication is given of total cost. Reliability o f s w l t c h i ~ g networ]ks for i m p e d / m e n t of trunk lines. M. AKIYAMAand A. HASHIMOTO,Trans.
WORLD
ABSTRACTS
ON MICROELECTRONICS
offer more protection from mechanical abrasions and foreign materials. Some electrical parameters of transistors as well as integrated circuits were measured before and after paesivation; no significant differences were f o u n d ~ l o degradation on these parameters was found after a*|000-hr operating life test on pasaivated and non-passiv#ted units. R e l i a b i l i t y Q hybrid m i ~ t s i n use today. R. J. STaAtm, Proc. 1970 20th Electronic Component: Conf., Washington, 13-15 May (1970), p. 16. Results of testing nearly 125,000 hybrid microcircuits from eight manufacturers show the need for formal testing and screening to avoid potential quality and reliability problems. The units were tested by AC Electronics from 1967 to late 1969. The resultant data was gathered and analyzed as part of an Air Force study contract. Information presented in this paper includes the test procedures imposed on the microcircuit suppliers before shipment, as well as those performed after delivery at AC Electronics. Test data are summarized relative to receiving-inspection, sample inspection and environmental testing, extended performance testing and subsequent assembly and field performance. The continued need for new evaluation techniques is further evidenced by results of stepped stress mechanical and environmental testing, performed per MIL-STD-883 under the referenced Air Force study contract on three different hybrid circuits from three manufacturers. The observed on-aircraft failure rate of hybrid microcircuits subjected to this controlled processing and testing through November 1969 was 0-465 failures per 1,000,000 hr. This failure rate has a 90 per cent confidence interval of 0.218 to 0-874 failures per 1,000,000 hr. It pertains to 3, C I R C U I T A N D S Y S T E M S R ] ~ J A B I I A ~ , P o w e r s y s t e m reliability evaluation. R. BILLINTON, Int. y. Engng F_,Juc. 8 (1970), p. 467. Quan6tative reliability evaluation is becoming increasingly important in the economic appraisal of alternate engineering facilities. Reliability has often been expressed in qualitative terms which do not readily lend themselves to system optimization, particularly where digital computers are utilized. A graduate course on reliability engineering of one term's duration was introduced in the Electrical Engineering Department at the University of Saskatchewan in 1965. This course has proved quite successful and has been attended by approximately equal numbers of graduate students from the Mechanical and Electrical Departments. Some of this material has also been briefly introduced into an undergraduate course taken by electrical engineering students. In 1967 a one-term graduate course entitled "Power System Reliability" was introduced into the graduate program. This course supplements the existing graduate classes presently given in the power systems area. Compare
reliability at a glance.
C. H. K A ~ ,
Electron. Des. 18, September (1970), p. 69. System
AND RELIABILITY
hybrid microcircuits used on aircraft and a missile. These circuits were exposed to mechanical shock, vibration, temperature cycling, and all of the other environments present outside of the pressurized, temperaturecontrolled cabin of the vehicle.
Tramdent a, m e a l i n g of d e f e c t s i n i r r a d i a t e d silicon d e v i c e s . B. L. GI~GORY and H. H. S A N ~ , Proc.
IEEE$8, No. 9, September (1970), p. 1328. The annealing of radiation-produced defects in semiconductor devices is discussed briefly for e°Co gamma-ray and 1-MeV clectron damage, and in detail for fast-neutron damage. The effects on the re-ordering processes of varying the material parameters and the irradiation conditions are considered. Transient annealing of neutron damage near room temperature has been investigated for a wide variety of devices, and the data are presented in generalized form to increase their usefulne~ to device and circuit designers. Based on the experimental results, physical models are suggested for the re-ordering processes which occur during the annealing of neutron damage. Electron density is shown to be the most important factor governing the rate of transient annealing. Annealing factors are estimated for very early times (1 ~ ) following neutron exposure. Suggestions are made to minimize the effects of transient annealing on devices. ReliabiliW testing. R. G. RAUTH et al., Eva. Engng 8, No. 5, September-October (1969), pp. 14, 15. RCA's approach to the IC specification in action helping to produce more reliable products is described. The four reliability screening levels based on Mil-Std-883 are given. MAINTENANCE
AND RF~UNDANCY
reliability can be improved by using redundant components, and its numerical value can be calculated by using the binomial expansion. However, the analytic approach can be tedious. A set of computer-generated curves that makes system reliability comparisons possible at a glance is given. The curves can be applied to two types of redundancy calculation: back-up and back-off. Back-up redundancy means that incremental or fractional spares are available to replace failed units in order to maintain a given capability. Back-off redundancy refers to the probability of meeting a degraded requirement--something less than a desired goal. L o w - c o s t v i d e o distribution a m p l i f i e r g i v e s inc r e a s e d reliabili W. G. A. STeve~, E/e~tron. Engng, October (1970), p. 47. Design details are given for a video distribution amplifier which can be used in any required mode, and in the simplest possible manner. Constructional requirements are outlined and an indication is given of total cost. Reliability o f s w l t c h i ~ g networ]ks for i m p e d / m e n t of trunk lines. M. AKIYAMAand A. HASHIMOTO,Trans.