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Integrated circuit production yield assurance based on yield analysis
1950
World abstracts of microelectronics and reliability
a Debye-type relaxation of the compensation regions at the grain boundaries, with time constant r ~ 15 ms. Good agreement between theory and experiment is obtained over the 0 to 1500 V bias range.
Lowering manufacturing defects analysis costs. MARTYN MANN. Test and Measurement Europe, 37 (Autumn 1993). Manufacturers handling high volumes of a few PCB types can usually cost-justify an ATE system to monitor production processes and diagnose faults. But even for these companies the cost of test programs and fixtures is high enough to make this approach impractical for short production runs. To handle such situations, sub-contract manufacturer Offshore Electronics, Guernsey, U.K., recently augmented an in-circuit production-test strategy. They adopted a Polar Instruments analog impedance-signature analyzer, significantly reducing the time and cost of component-level diagnosis.
Corrosion of thin film aluminum metallization: eonformal coating materials. J. S. OSENBACHand J. L. ZELL. I E E E Transactions on Components, Hybrids and Manufacturiny Technoloyy, 16(3), 350 (May 1993). We report our results on the THB performance of triple-track-tester (TTT) devices coated with room temperature vulcanized silicon rubber (RTV), silicon resin, silicon polyimide, or silicon gel. Devices with each of these conformal coating materials were aged at 85 C/85~°,; relative humidity (r.h.)/A, where 40 ~ A ~ 400 V, for times up to 14,000 hr. We found that the median time-to-fail was exponentially related to the applied voltage. The median life at 300 V was in excess of 30,000 hr for the silicon gel coated samples, 10,000 hr for the RTV coated samples, 3000 hr for the silicon resin coated samples, and 2000hr for the polyimide coated samples. The difference in the median life times is due to differences in the interface bond strength between the polymer coat and the device surface.
Microcurrent, ultra-miniature switches offer reliable contact. TADASHINAKAMURA.JEE (Japan), 38 (June 1993). The trend toward small, thin and lightweight products now includes the switches that play an important role in electronic equipment. The function, performance and quality of the switches improves every year. With the growing number of electronic switches, there is a large demand for switches that operate on low voltage and microcurrents. In addition to their primary use in computer peripheral devices, switches are serve in many different areas such as office automation (OA) equipment, communication equipment and medical equipment.
Systems adopt advanced technology for testing IC devices. OSAMU YAMADA et al. JEE (Japan), 79 (September
1993). Classifications group ICs by
function and application, resulting in three catagories covering memory ICs, logic ICs and mixed-signal ICs. Testing these devices represents an important and traditionally time-consuming step in semiconductor production. Recently, testing systems have evolved that offer superior reliability and speed. Among the participants in this market, Advantest Corp. markets IC test systems for uses from research and development (R & D) to semiconductor manufacturing. This article outlines the latest trends in test technology, and describes specific semiconductor test systems.
A systematic evaluation of factors influencing TAB inner lead reliability. H. E. EVANS, P. M. HARVEY, J. L. DABROSKI and G. O. DEARING. Circuit World, 19(4), 40 (July 1993). Reliability evaluations for new electronic components and assemblies regularly require extensive test cycles that are both time consuming and costly. Objectives of such test batteries are to identify failure mechanisms and the relationship between these mechanisms and product design or processing features. Optimisation of these critical factors or process steps results in optimised reliability. Statistically designed experiments can facilitate the optimisation process by minimising the amount of testing needed to identify factors affecting reliability, and by providing insight into how these factors can be specified to ensure optimum product design. Designed experimentation was utilised in this study to look at product design and process factors affecting the reliability of inner leads for tape automated bonding (TAB) components. Four factors are considered: outer lead compliancy; chip immobilisation: downset; and tape stiffness and rigidity. Experimental details and results are presented which assess the relative importance of these factors in determining ultimate inner lead reliability, and also provide guidance for final product design considerations.
Printed wiring boards with silver through-holes help lower costs. JEE (Japan), 55 (November 1993). Manufacturers today face rising demands to accommodate densely printed wiring boards while simultaneously lowering costs. Against this backdrop, the market for silver through-hole printed wiring boards is extended into various fields. With annual growth, the market already accounts for 300,000sq.m of boards a month. Such printed wiring boards face continuing expansion in the future. Accordingly, manufacturers will improve the technologies for these boards, develop new models, and apply them in innovative ways.
Integrated circuit production yield assurance based on yield analysis. Z. STAMENKOVICet al. Microelectronics Journal, 24, 819 (1993). The production of modern integrated circuits must be accompanied by control of the critical process steps, modern integrated circuit
World abstracts on microelectronics and reliability production control being based on yield analysis. It is shown in this paper that yield analysis can also be used to ensure efficient investments and predict investments which are required in order to ensure a competitive yield of future products.
Communication requirements spur changes in small chip filters, ceramic resonators. YOSHITSUGAATSUTA. JEE (Japan), 48 (November 1993). As sets continue to grow smaller, thinner and lighter than their predecessors, demand rises for compact, advancedperformance components that adopt surface mount device (SMD) formats. The communications sector represents a rapidly growing field within the electronics industry, and here manufacturers face strong demand for compact piezoelectric filters and ceramic resonators. To meet these demands, it is necessary to refine existing technologies and cultivate new ones. Products from Murata Manufacturing provide examples of some of the latest trends in chip components.
Failure analysis of power modules: a look at the packaging and reliability of large IGBT's. HERVE DE LAMBILLY and HELMUT O. KESER. IEEE Transactions on Components, Hybrids and Manufacturing Technolo,qy, 16(4), 412 (June 1993). Processing yield limits today's MOS power chip sizes to a few square centimeters. This introduced a new family of power modules made of several paralleled chips. In this paper, the reliability of such assemblies will be checked with power cycling tests and the inhomogeneities in temperature inside the module presented.
Reliability of surface-mounted anisotropically conductive adhesive joints. J. LIu. Circuit World, 19(4), 4 (July 1993). The purpose of the work is to investigate the feasibility of using anisotropically conductive adhesives to join surface-mount devices as solder replacement. The results from a literature and market survey are reported. Based on industrial demands, two anisotropically conductive adhesives were chosen for the experimental work. During the experimental work, the conductive adhesive joints were produced at various curing conditions. The joints were characterised by shear testing and electrical resistance measurement after ageing at 20, 70 and 120°C to 1000hr. Optical and scanning electron microscopy were used to characterise the adhesive joints. In addition to this, temperature cycling tests, humidity test and pull tensile tests were used to qualify the adhesive joint reliability and quality. From the results of the present work, it can be concluded that the anisotropically conductive adhesive A joints are stable in the 85°C/85~, r.h. environment and therefore have better corrosion resistance than adhesive B joints. Neither of the adhesives can pass temperature cycling
1951
from - 5 5 to 125°C for 1000 cycles according to military standard 883C.
Large capacitance electric double layer capacitor using activated carbon-carbon composite. JUNJI TABUCHI et al. IEEE Transactions on Components, Hybrids and Manufacturing Technology, 16(4), 431 (June 1993). An electric double layer capacitor with large capacitance, 1000 F at 5.5 V, has been developed. It uses activated carbon-carbon (AC/C) composite as the polarizable electrodes and sulfuric acid as the electrolyte. The AC/C composite was synthesized through a simple process, namely a cured mixture of activated carbon and phenol-formaldehyde resin was carbonized. The A C - C composite has a large surface area, 1300 m2/g, and low resistivity, 0.01f2. cm. Two kinds of pores exist in the A C - C composite, macropores with submicrometer diameters, and micropores with below 4-nm diameter. A sulfuric acid aqueous solution, as an electrolyte, is impregnated into the micropores through the macropores open to the outer surface. The electric double layer capacitance per unit volume for the A C - C composite in sulfuric acid is greater than that for activated carbon powder as a raw material. The electric double layer capacitor with large capacitance using the A C - C composite is expected to be used as a new energy storage device and a new supplementary power source.
Infrared thermography maintains PCB reliability. DAVID SMITH. Test and Measurement Europe, 33 (Autumn 1993). Engineers at IBM's component engineering laboratory, located in Greenock, Scotland, have adopted an unusual technique for testing PCBs on prototype computer monitors to ensure final product quality. The technique, called infrared thermography, measures the temperature of any object or group of objects without making physical contact. Scanning cameras detect the invisible i.r. radiation emitted by the object under test. Special electro-optics in the scanner convert this radiation into video signals for storage or display on a Super Video Graphics Adapter monitor. A continuous grey scale or 256-color palette permits easy identification of the temperature of different points on the object. In addition to providing static images, some cameras record transient events in real time. This technique is particularly useful for monitoring a board's bonded heat sinks and component-cooling profile during normal operation.
Torsional stiffness and fatigue study of surface-mounted compliant leaded systems. PETER A. ENGEL and TIMOTHY M. MILLER. IEEE Transactions on Components, Hybrids and Manufacturing Technology, 16(6), 577 (September 1993). Circuit cards with surface-soldered compliant leaded modules are often subjected to torque tests to ensure their structural
World abstracts of microelectronics and reliability
a Debye-type relaxation of the compensation regions at the grain boundaries, with time constant r ~ 15 ms. Good agreement between theory and experiment is obtained over the 0 to 1500 V bias range.
Lowering manufacturing defects analysis costs. MARTYN MANN. Test and Measurement Europe, 37 (Autumn 1993). Manufacturers handling high volumes of a few PCB types can usually cost-justify an ATE system to monitor production processes and diagnose faults. But even for these companies the cost of test programs and fixtures is high enough to make this approach impractical for short production runs. To handle such situations, sub-contract manufacturer Offshore Electronics, Guernsey, U.K., recently augmented an in-circuit production-test strategy. They adopted a Polar Instruments analog impedance-signature analyzer, significantly reducing the time and cost of component-level diagnosis.
Corrosion of thin film aluminum metallization: eonformal coating materials. J. S. OSENBACHand J. L. ZELL. I E E E Transactions on Components, Hybrids and Manufacturiny Technoloyy, 16(3), 350 (May 1993). We report our results on the THB performance of triple-track-tester (TTT) devices coated with room temperature vulcanized silicon rubber (RTV), silicon resin, silicon polyimide, or silicon gel. Devices with each of these conformal coating materials were aged at 85 C/85~°,; relative humidity (r.h.)/A, where 40 ~ A ~ 400 V, for times up to 14,000 hr. We found that the median time-to-fail was exponentially related to the applied voltage. The median life at 300 V was in excess of 30,000 hr for the silicon gel coated samples, 10,000 hr for the RTV coated samples, 3000 hr for the silicon resin coated samples, and 2000hr for the polyimide coated samples. The difference in the median life times is due to differences in the interface bond strength between the polymer coat and the device surface.
Microcurrent, ultra-miniature switches offer reliable contact. TADASHINAKAMURA.JEE (Japan), 38 (June 1993). The trend toward small, thin and lightweight products now includes the switches that play an important role in electronic equipment. The function, performance and quality of the switches improves every year. With the growing number of electronic switches, there is a large demand for switches that operate on low voltage and microcurrents. In addition to their primary use in computer peripheral devices, switches are serve in many different areas such as office automation (OA) equipment, communication equipment and medical equipment.
Systems adopt advanced technology for testing IC devices. OSAMU YAMADA et al. JEE (Japan), 79 (September
1993). Classifications group ICs by
function and application, resulting in three catagories covering memory ICs, logic ICs and mixed-signal ICs. Testing these devices represents an important and traditionally time-consuming step in semiconductor production. Recently, testing systems have evolved that offer superior reliability and speed. Among the participants in this market, Advantest Corp. markets IC test systems for uses from research and development (R & D) to semiconductor manufacturing. This article outlines the latest trends in test technology, and describes specific semiconductor test systems.
A systematic evaluation of factors influencing TAB inner lead reliability. H. E. EVANS, P. M. HARVEY, J. L. DABROSKI and G. O. DEARING. Circuit World, 19(4), 40 (July 1993). Reliability evaluations for new electronic components and assemblies regularly require extensive test cycles that are both time consuming and costly. Objectives of such test batteries are to identify failure mechanisms and the relationship between these mechanisms and product design or processing features. Optimisation of these critical factors or process steps results in optimised reliability. Statistically designed experiments can facilitate the optimisation process by minimising the amount of testing needed to identify factors affecting reliability, and by providing insight into how these factors can be specified to ensure optimum product design. Designed experimentation was utilised in this study to look at product design and process factors affecting the reliability of inner leads for tape automated bonding (TAB) components. Four factors are considered: outer lead compliancy; chip immobilisation: downset; and tape stiffness and rigidity. Experimental details and results are presented which assess the relative importance of these factors in determining ultimate inner lead reliability, and also provide guidance for final product design considerations.
Printed wiring boards with silver through-holes help lower costs. JEE (Japan), 55 (November 1993). Manufacturers today face rising demands to accommodate densely printed wiring boards while simultaneously lowering costs. Against this backdrop, the market for silver through-hole printed wiring boards is extended into various fields. With annual growth, the market already accounts for 300,000sq.m of boards a month. Such printed wiring boards face continuing expansion in the future. Accordingly, manufacturers will improve the technologies for these boards, develop new models, and apply them in innovative ways.
Integrated circuit production yield assurance based on yield analysis. Z. STAMENKOVICet al. Microelectronics Journal, 24, 819 (1993). The production of modern integrated circuits must be accompanied by control of the critical process steps, modern integrated circuit
World abstracts on microelectronics and reliability production control being based on yield analysis. It is shown in this paper that yield analysis can also be used to ensure efficient investments and predict investments which are required in order to ensure a competitive yield of future products.
Communication requirements spur changes in small chip filters, ceramic resonators. YOSHITSUGAATSUTA. JEE (Japan), 48 (November 1993). As sets continue to grow smaller, thinner and lighter than their predecessors, demand rises for compact, advancedperformance components that adopt surface mount device (SMD) formats. The communications sector represents a rapidly growing field within the electronics industry, and here manufacturers face strong demand for compact piezoelectric filters and ceramic resonators. To meet these demands, it is necessary to refine existing technologies and cultivate new ones. Products from Murata Manufacturing provide examples of some of the latest trends in chip components.
Failure analysis of power modules: a look at the packaging and reliability of large IGBT's. HERVE DE LAMBILLY and HELMUT O. KESER. IEEE Transactions on Components, Hybrids and Manufacturing Technolo,qy, 16(4), 412 (June 1993). Processing yield limits today's MOS power chip sizes to a few square centimeters. This introduced a new family of power modules made of several paralleled chips. In this paper, the reliability of such assemblies will be checked with power cycling tests and the inhomogeneities in temperature inside the module presented.
Reliability of surface-mounted anisotropically conductive adhesive joints. J. LIu. Circuit World, 19(4), 4 (July 1993). The purpose of the work is to investigate the feasibility of using anisotropically conductive adhesives to join surface-mount devices as solder replacement. The results from a literature and market survey are reported. Based on industrial demands, two anisotropically conductive adhesives were chosen for the experimental work. During the experimental work, the conductive adhesive joints were produced at various curing conditions. The joints were characterised by shear testing and electrical resistance measurement after ageing at 20, 70 and 120°C to 1000hr. Optical and scanning electron microscopy were used to characterise the adhesive joints. In addition to this, temperature cycling tests, humidity test and pull tensile tests were used to qualify the adhesive joint reliability and quality. From the results of the present work, it can be concluded that the anisotropically conductive adhesive A joints are stable in the 85°C/85~, r.h. environment and therefore have better corrosion resistance than adhesive B joints. Neither of the adhesives can pass temperature cycling
1951
from - 5 5 to 125°C for 1000 cycles according to military standard 883C.
Large capacitance electric double layer capacitor using activated carbon-carbon composite. JUNJI TABUCHI et al. IEEE Transactions on Components, Hybrids and Manufacturing Technology, 16(4), 431 (June 1993). An electric double layer capacitor with large capacitance, 1000 F at 5.5 V, has been developed. It uses activated carbon-carbon (AC/C) composite as the polarizable electrodes and sulfuric acid as the electrolyte. The AC/C composite was synthesized through a simple process, namely a cured mixture of activated carbon and phenol-formaldehyde resin was carbonized. The A C - C composite has a large surface area, 1300 m2/g, and low resistivity, 0.01f2. cm. Two kinds of pores exist in the A C - C composite, macropores with submicrometer diameters, and micropores with below 4-nm diameter. A sulfuric acid aqueous solution, as an electrolyte, is impregnated into the micropores through the macropores open to the outer surface. The electric double layer capacitance per unit volume for the A C - C composite in sulfuric acid is greater than that for activated carbon powder as a raw material. The electric double layer capacitor with large capacitance using the A C - C composite is expected to be used as a new energy storage device and a new supplementary power source.
Infrared thermography maintains PCB reliability. DAVID SMITH. Test and Measurement Europe, 33 (Autumn 1993). Engineers at IBM's component engineering laboratory, located in Greenock, Scotland, have adopted an unusual technique for testing PCBs on prototype computer monitors to ensure final product quality. The technique, called infrared thermography, measures the temperature of any object or group of objects without making physical contact. Scanning cameras detect the invisible i.r. radiation emitted by the object under test. Special electro-optics in the scanner convert this radiation into video signals for storage or display on a Super Video Graphics Adapter monitor. A continuous grey scale or 256-color palette permits easy identification of the temperature of different points on the object. In addition to providing static images, some cameras record transient events in real time. This technique is particularly useful for monitoring a board's bonded heat sinks and component-cooling profile during normal operation.
Torsional stiffness and fatigue study of surface-mounted compliant leaded systems. PETER A. ENGEL and TIMOTHY M. MILLER. IEEE Transactions on Components, Hybrids and Manufacturing Technology, 16(6), 577 (September 1993). Circuit cards with surface-soldered compliant leaded modules are often subjected to torque tests to ensure their structural