Revised Test Methods Research Articles

JEDEC's Generation of Wire Bond Pull Test Methods to Address Pulling of Copper Wire Bonds

Abstract More than 50 years ago when the wire pull test method was initially added to Mil-Std 883, in Condition D of Method 2011, Bond Strength (Destructive Bond Pull Test), the test procedure and minimum pull force values were based on pull testing of mostly ultrasonic wedge bonded aluminum and gold wires of just a few different diameters. The minimum pull force values from that original data were extrapolated to cover a much wider range of wire diameters for both gold and aluminum wires. Since the release of this test method the electronics industry has manufactured copper ultrasonic wedge bonds, widely adopted copper thermosonic ball bonding roughly 15 years ago, and even developed a niche market for silver thermosonic ball bonding. The industry also developed specialty bonds such as security bonds, reverse bonds also called "stitch on ball", and even multi-loop wires and ribbons. In all that time neither the test procedure nor the minimum pull force values in Method 2011 were reviewed to determine their appropriateness for these new materials or new types of bonds, even though the industry widely referenced the test method for all of them and thus, by default, accepted its use for all of them. In late 2013, I led a working group within JEDEC's JC14.1 subcommittee, Reliability Test Methods for Packaged Devices, to update JEDEC JESD22-B116, Ball Bond Shear Test Method, to expand its scope to include the shearing of Cu ball bonds. It took the working group three years to address the necessary technical issues to ensure that the revised test method adequately addressed the shearing of copper ball bonds and propose minimum acceptable shear values. The working group produced a greatly improved document with drawings and images depicting the different shear fail modes of both gold and copper bonds and added several informative annexes to aid in the performing of the test method. By 2018 it was apparent that none of the most commonly referenced wire pull test methods in the electronics industry had made any significant progress in updating their documents to include Cu wire bonds. Therefore, the JC14.1 working group agreed to work jointly with the JC-13.7 Subcommittee, New Electronic Device Technology, to create a new, wire pull test method document under JC14.1 that would be a companion to the JESD22-B116. This new document will use Method 2011, Conditions C and D as its basis, but expand on its scope to cover copper wire bonds, both ultrasonic wedge and thermosonic ball bonds. The new test method will describe the process for a ball pull test and a stitch pull test that are referenced for copper bonds by AEC Q006, Qualification Requirement for Component Using Copper (Cu) Wire Interconnection. The test method will also provide guidance on how to perform pull testing on several different bond types used today including reverse bonds, multi-loop bonds, and stacked die. The working group plans to propose minimum pull values for copper wire bonds which JC14.1 will reference in JESD47, Stress-Test-Driven Qualification of Integrated Circuits. After the joint working group completes its work, which is targeted for some time in 2022, JC13.7 would then be able to use the output of this working group to update Method 2011 Conditions C & D. This paper will first briefly discuss the updates made to B116 to cover Cu wire bonds, but mainly focus on the work that has so far been completed by the joint working group, including a general outline of the proposed new document, JESD22-B120, Wire Bond Pull Test Methods.

Results of a laboratory round robin for ASTM International Standard E477-13 for duct silencers

ASTM International initiated a laboratory round robin in November 2014 to support the development of a precision and bias statement for the recently revised standard E477-13. Two different silencer designs were constructed for testing by 5 participating laboratories. This paper will discuss the revised test method, the test results, and identify future modifications to the standard that should be looked at in the future.

Development of a new test cell to measure cumulative permeation of water-insoluble pesticides with low vapor pressure through protective clothing and glove materials.

A collaborative approach, involving resources and expertise from several countries, was used to develop a test cell to measure cumulative permeation by a solid-state collection technique. The new technique was developed to measure the permeation of pesticide active ingredients and other chemicals with low vapor pressure that would otherwise be difficult to test via standard techniques. The development process is described and the results from the final chosen test method are reported. Inter-laboratory studies were conducted to further refine the new method and determine repeatability and reliability. The revised test method has been approved as a new ISO/EN standard to measure permeation of chemicals with low vapor pressure and/or solubility in water.

Characterization of Absorbent Flow Rate in Towel and Tissue

The quality of a paper towel is often judged based on how quickly it can wipe up a spill. However, the test methods currently available cannot repeatably measure significant differences in absorbent rate between samples. Recent round-robin testing evaluations by TAPPI and CEN organizations have shown that past methods, such as ASTM D5802–95 and TAPPI T561-pm [1], are unreliable due to high variability. The reasons for the lack of repeatability are unclear. The relation between the wicking mechanism and the fundamental absorbent properties needs to be better understood. This paper uses x-ray imaging to show the overall flow characteristics of fluid absorption within a towel, and compares the results to model predictions to show which parameters are important to the process. From this understanding, a revised test method is proposed that provides adequate statistical discernment of absorbent rate properties of tissue on a simple lab-bench scale device.

실내 공기질 공정시험방법과 기준의 동시 개정에 따른 실란트 제품의 TVOC 관리수준 평가

환경부에서는 오염물질 다량 방출 건축자재의 효율적인 관리를 위해 다중이용시설 등의 실내 공기질 관리법의 시행 규칙 일부를 개정하였다. 특히 액상건축 자재인 실란트의 경우 시험방법과 초과기준이 함께 개정되어 기존 관리 수준과 개정 관리 수준의 직접적인 비교가 불가능하다. 따라서 이 연구에서는 실란트의 개정 시험방법의 각 요소들이 오염물질 방출강도에 미치는 영향과 타당성을 기존 시험방법에 대비하여 검토하였다. 이를 통하여 개정된 오염물질 방출 관리기준을 평가하였다. 특히 실란트는 제품마다 완전경화에 소요되는 시간의 편차가 커서 시험기간 내에 완전히 경화되지 않는 제품들도 다수 있는 것으로 나타났다. 그래서 경화시간이 빠른 제품들만 대상으로 개정된 시험방법을 적용하여 실험하였다. 그 결과 개정된 실란트의 관리기준은 기존의 관리기준에 비해 2.5 배 이상 약화된 것으로 나타났다. 개정된 실란트의 시험방법을 모든 실란트 제품에 적용하기 위해서는 시험기간을 연장하거나 실란트 시험편을 빨리 경화시킬 수 있는 시험방법으로 개선이 필요하다. The Korean Ministry of the Environment revised a few sections of the regulations in the Law of indoor air quality management for the reinforcement or adjustment of the regulation criteria standard for releasing pollutants from building materials. Especially, in case of sealant, the contents covering liquid building materials, excess standards and testing methods have been added simultaneously in this revision, As a result it is impossible to compare original standards with revised standards directly. For this reason, this study reviewed revised test method of sealant pollutant emission rates in terms of impact and validity in comparison with the original test method. Through this study, the basic properties of revised pollutant emission control standards was assessed. Especially in sealant, since each product has a wide deviation of time required for complete drying, it is proved that there are a large number of products that are not hardened completely in test time. The result of our experiments on the revised test methods showed that this revised test methods yield emission rates that are two and half times less than those of the original testing method. To apply the revised test method of sealant to all the sealant products, It is necessary to extend the test period or improve specimen to fit the test method for quickly drying sealant products.

Standardizing the Measurement of Minimum Extinguishing Concentrations of Gaseous Agents

The cup-burner test method has had a long history as a tool for measuring the minimum flame extinguishing concentrations (MEC) of gaseous fire-extinguishing agents for flammable and combustible liquid fuels. The pioneering work by Hirst and Booth (1977) set out the basic principles of the cup-burner and its use. Saso et al. (1993) reported on scale effects on MEC measurement. Preece et al. (2003) reported on parametric effects on MEC measurement. A number of investigators have provided determined values of MEC for a number of inert gas and fluorocarbon agents. See Dlugogorski et al. (1996); Saito et al. (1996); Moore et al. (1998); Sheinson et al. (1998). Takahashi et al. have reported on several investigations of flame extinguishment in the cup-burner including conducting a detailed computational fluid dynamic modeling including reaction kinetics and mass and heat transfer (2003); physical and chemical aspects of flame extinguishment (May 2005); and evaluation of flame extinguishment in low gravity (January 2005). Application of the cup-burner method has, in some instances, produced inconsistent results. MEC values reported by several investigators for the same inert gas agents have exhibited differences that are significant with respect to the way in which they are used (Senecal 2005). Thermochemical analysis and data obtained in a consistent manner suggested that there is a reasonable basis to expect highly consistent, and even predictable, MEC values for inert gas agents. It appeared that the likely source of measurement variation was due to procedural and mechanical differences in the conduct of the cup-burner test among various laboratories. A Task Group, appointed by the NFPA GFE-AAA technical committee on gaseous fire-extinguishing systems, revised the cup-burner test procedure including the specification of a standardized test apparatus. This article describes an inter-laboratory study conducted in 2006 to (1) determine consensus value benchmark minimum extinguishing concentrations (MEC) of an inert gas agent and a halocarbon agent; (2) evaluate the reproducibility of the revised test method; and (3) evaluate the day-to-day consistency (repeatability) of the test method. The results of an inter-laboratory (round robin) study have established benchmark MEC values for nitrogen and HFC-227ea with excellent reproducibility. The results show that MEC values reported by most laboratories were in very good agreement, i.e., exhibited good reproducibility based on averages of three replicate determinations on different days. Analysis of the replicate data revealed a variable degree of repeatability, suggesting that a laboratory will need to review key procedural details in some cases.

A selection of papers from an international meeting on: advances in multi-scale modelling of composite material systems & components

The driving force to get new lightweight composite materials into the air comes from the increasing cost of fuel worldwide. An airline industry’s response to higher fuel charges is to make aircraft lighter and fuel efficient. What appears to be a paradox is that as the cost of fuel is going up, so is the size of airframe; the new Airbus superjumbo A380 is an example. New composite materials including those based on carbon fibre (CFRP) and the glass fibre-metal laminate called GLARE are replacing aluminium alloys, and modern civil airliners like Boeing’s brand new Dreamliner 787 and the Airbus A350 may contain up to 50% by weight of composite material. The infrastructure required to support these new advances includes: fibre production and resin processing, manufacture of innovative fibre pre-preg architecture, new machine tools and assembly jigs, advanced fabrication processes and factory-of-the-future design, structure formulation of composite material systems, and revised test methods. In addition, is the need for improved design techniques to optimise airframe layout thereby maximising acceptable (safe) working loads. And at the same time, we must reduce fabrication costs through automation and low temperature curing matrix systems, and certify practical advanced inspection techniques for defect detection and repair. Demands in modern aircraft include efficient aerodynamic design and lightweight materials combined with high efficiency engines to fly the aircraft, and providing electrical power for all the electrical systems. Keeping cost down is essential, which can only be achieved by using less fuel and reducing dramatically maintenance expense. The expectation is for materials to last longer and for structures to operate safely and reliably at increasingly higher stresses. In the case of engine components, we expect the material to work successfully at greater elevated temperature. The requirement is to push the performance of the structure to its limit thereby stretching composite materials to their boundary of strength and endurance. Innovation in design and advancement in material ‘‘know-how’’ through discovery is no longer the single option. We see airframes made from composites, arriving at the probability of a successful outcome of a safe design by using intuition and our experience of circumstances that we have encountered before. But if we are to imagine the future differently, disaster as an act of God or of bad luck has to go. Predictive engineering design by intelligentinformed empiricism is the only ‘‘show in town’’. There has been an invisible college of continuum mechanicians, scattered in universities, who have for decades studied the behaviour of composite materials based on an idealization of what behaviour is all about, and coming up with countless models without any reference whatsoever to microstructure; neither have they cared about mechanisms that act at the small end of the size-scale, nor structurally-based constitutive equations. Consequently, current design codes for composite material structures in critical loading situations do not take creep, fatigue and environmental-induced mechanisms into account. To predict a result, say lifetime or a stress P. W. R. Beaumont (&) Engineering Department, Cambridge University, Trumpington Street, Cambridge CB2 1PZ, UK e-mail: pwb1000@hermes.cam.ac.uk J Mater Sci (2006) 41:6505–6509 DOI 10.1007/s10853-006-0209-2

Improvements in the Measurement of Cut Protection Performance: Revisions to ASTM F 1790

Abstract Workers exposed to mechanical hazards that could cause cuts or lacerations to the hands and arms have a need to understand the cut protection performance of protective apparel. Cut protection performance of clothing can be measured using CEN 388, ASTM International standard F 1790-97, and ISO 13997. The ASTM and ISO test methods employ force-distance testers to determine the cut resistance of a material when exposed to a cutting edge under specified loads. The latter two test methods provide a process for differentiating the cut protection performance of various materials such as cotton, leather, and high performance fibers. ASTM task group F23.20.02 sought to improve the reliability and reproducibility of the F 1790-97 standard in a way that creates a global standard for measuring cut performance, demonstrates equivalence of results between different test equipment, and reduces variability in the test method. The revised test method has been balloted by the main and sub-committees for adoption. This paper will outline the results of extensive interlaboratory studies on the test equipment, calibration method, and calibration materials. The implications of other testing aspects on the harmonization of the standards will be described. This information will be useful for end users, distributors, and manufacturers interested in measuring the cut performance of clothing.

Flame Resistant Barriers for Home Furnishings

California’s Assembly Bill 603 (AB603), requiring all bed sets manufactured for sale in the State of California comply with new open-flame resistant (FR) standards, was passed on August 10, 2001. A revised test method, California Test Bulletin 603 (TB603) and pass/fail criteria were announced in July 2003. The California’s bureau of home furnishings and thermal insulation (CBHFTI) is in the process of finalizing its ruling for mandatory compliance with this standard by January 2005. Although the timing of a national FR standard for bed sets with the Consumer Product Safety Commission (CPSC) has not been set, an Advanced Notice for Proposed Rulemaking (ANPR) was announced in October 2001. In July 2003, CPSC staff recommended that another ANPR be issued for a FR standard for upholstered furniture. FR barrier technologies, which utilize no FR chemicals or coatings, have been developed to comply with TB603 and have also been tested in upholstered furniture applications. This paper details some of the statistics behind the effort to develop safe and effective open-flame resistant home furnishings and summarizes the latest developments in FR barrier technology utilizing Basofil® fiber. Test results in both bedding and upholstered furniture applications are also presented.

Humane Endpoints for Laboratory Animals Used in Regulatory Testing

Laboratory animals are used for regulatory testing to assess the safety, efficacy, and/or potential adverse health effects of new chemicals and products such as vaccines, medicines, food additives, pesticides, and industrial chemicals. Testing results are used for risk assessment decisions intended to safeguard human and animal health. However, chemical toxicity and vaccine testing can cause injury, disease, and mortality involving significant pain and distress. Alleviation of pain and distress in animals during testing is problematic because regulations allow treatment only if the treatment does not interfere with the study. One approach to this problem has been to identify criteria that can serve as the basis for ending a test procedure sooner in an effort to terminate or avoid pain and distress while still allowing attainment of study objectives. These criteria are referred to as humane endpoints because they reduce the severity and/or duration of pain and distress experienced by an animal. New and revised test methods and approaches that incorporate humane endpoints are being considered and adopted by national and international regulatory testing authorities. The prerequisite for adoption of these methods is a determination that the methods have been adequately validated and that they provide equivalent or better information for risk assessment. Further progress in reducing animal pain and distress resulting from regulatory testing is expected as scientific and technological advances are incorporated into testing procedures and strategies.

ICCVAM Evaluation of the Murine Local Lymph Node Assay: I. The ICCVAM Review Process

New test methods are being developed to improve the prediction of human and environmental risks and to benefit animal welfare by reducing, refining, and replacing animal use. Regulatory adoption of new test methods is often a complex and protracted process, requiring test method validation, regulatory acceptance, and implementation. Assessments of new test methods have not always been uniform within or among regulatory agencies. Thus, there have been increased pressures for a harmonized approach to test method evaluation and acceptance. In 1997, in response to these pressures and to U.S. Public Law 103-43, the National Institute of Environmental Health Sciences (NIEHS) established the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) to coordinate interagency consideration of new and revised test methods. This article describes the validation and acceptance criteria and process used for the first test method evaluated by ICCVAM, the murine local lymph node assay (LLNA). Based on ICCVAM's conclusions and recommendations, the LLNA has been accepted by U.S. regulatory agencies as a stand-alone assay for allergic contact dermatitis. Two related articles in this series of three present the results of the independent peer review evaluation of the LLNA and summarize the performance characteristics of the database substantiating the validity of the LLNA.

Evaluation of a Test Method for Measuring Indoor Air Emissions from Dry-Process Photocopiers

ABSTRACT A large chamber test method for measuring indoor air emissions from office equipment was developed, evaluated, and revised based on the initial testing of four dry-process photocopiers. Because all chambers may not necessarily produce similar results (e.g., due to differences in sink effects, temperature and humidity control, air exchange, pollutant monitoring, and measurement biases), a preliminary four-laboratory evaluation of the revised test method was conducted. To minimize variability, the evaluation used a single dry-process photocopier that was shipped to each of the four laboratories along with supplies (i.e., toner and paper). The results of this preliminary four-laboratory evaluation demonstrate that the test method was used successfully in the different chambers to measure emissions from dry-process photocopiers. Differences in chamber design and construction appeared to have had minimal effect on the results for the volatile organic compounds (VOCs). Perhaps more important than the chamber itself is the sample analysis as identified by duplicate samples that were analyzed by a different laboratory. Percent relative standard deviation (%RSD) was used to provide a simplistic view of interlaboratory precision for this evaluation. Excluding problems with suspected analytical bias observed from one of the laboratories, the precision was excellent for the VOCs with RSDs of less than 10% in most cases. Less precision was observed among the laboratories for aldehydes/ketones (RSD of 23.2% for formaldehyde). The precision for ozone emission rates among three of the laboratories was excellent (RSD of 7.9%), but emission rates measured at the fourth laboratory were much higher.

Particle Emissions from Gas Handling Components Measured According to the SEMATECH Test Methods

Particle emission rates measured from ultra-high purity, cleanroom gas handling components following the test procedures specified in the SEMATECH test methods are described. A condensation nucleus particle counter (CNC) having a counting efficiency of 50 percent at 0.02 μm in diameter was used to measure the total particle contribution from the gas handling components. A spool piece was inserted to measure the baseline particle concentration of the test stand before the measurement of the test component was carried out. Eighteen test samples, six each from three suppliers (two domestic and one foreign), in each type of gas handling components (valves, point-of-use filters, pressure regulators), were tested using the revised test method. Particle contribution data obtained for fresh out-of-the-bag, stainless steel (SS) test samples, 1/4-in. in OD, from different manufacturers are summarized in this paper.

Publication Sponsored by the Society's Fastness Tests Co‐ordinating Committee‐52 Colour Fastness to Chlorinated Water (Swimming Bath Water)

Results obtained using the current standard test (BS 1006‐.E03:1978) do not correspond adequately with the performance of representative dyeings from current ranges of fabrics used in chlorinated swimming pools. A revised test method is defined. It has been subjected to interlaboratory evaluation, to assess repeatability and reproducibility and compared with results from swimming pool trials. It has been shown to be satisfactory in both respects.