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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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This paper discusses limitation of each system and provides representative inspection images for CCGA/BGA assemblies.
This paper reports the results of an experiment that utilized the JPL's area array consortium test vehicle design, containing a myriad of mixed technology components with an OSP finish. The details of the reliability study are presented in this paper.
Area Array Packages (AAPs) with 1.27 mm pitch have been the packages of the choice for commercial applications; they are now started to be implemented for use in military and aerospace applications. Thermal cycling characteristics of plastic BGA (PBGA) and CSP assemblies, because of their wide usage for commercial applications, have been extensively reported in literature. Thermal cycling represents the on-off environmental condition for most electronic products and therefore is a key factor that defines reliability.
Commercial-off-the-shelf area array package technologies in high-reliability versions are being considered for NASA electronic systems. These packages are prone to early failure due to the severe mechanical shock and vibration of launch, as well as other less severe conditions, such as mechanical loading during descent, rough terrain mobility, handling, and ground tests. As the density of these packages increases and the size of ball interconnections decrease, susceptibility to mechanical loading and cycling fatigue grows. This report presents a summary of the body of knowledge developed for the evaluation of area array packages and is based on surveys of literature from industry and academia. For high-reliability applications, the limited data that exists will be presented. Most data from industry deals with mechanical fatigue caused by four-point bend tests, as well as from drop tests for hand-held electronics; the most recent data will be presented, along with a brief background of prior literature. Understanding the key design guidelines and failure mechanisms from past tests is critical to developing an approach that will minimize future failures. Additional specific testing enables low-risk insertion of these advanced electronic packages.
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Inspection results along with SEM and optical cross-sectional photos revealing damage and failure mechanisms will also be presented.
The test results for numerous chip scale package assembly performed under MicrotypeBGA Consortium led by the Jet Propulsion Laboratory have been published previously.
System in a package (SIP) development is a response to an increasing demand for integration of different functions into one unit to reduce size and cost and improve functionality. Qualification of the newly developed multifunctional electronics are becoming complex at the package level and even more at the second and system levels.
This paper will present cycles to failure in Weibull plots as well as their failure characteristics up to 7000 cycles.
This paper will present failure characteristics of the assemblies up to 7,000 cycles.
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C-mode scanning acoustic microscopy (C-SAM) is a nondestructive inspection technique that uses ultrasound to show the internal feature of a specimen. A very high or ultra-high-frequency ultrasound passes through a specimen to produce a visible acoustic microimage (AMI) of its inner features. As ultrasound travels into a specimen, the wave is absorbed, scattered or reflected. The response is highly sensitive to the elastic properties of the materials and is especially sensitive to air gaps. This specific characteristic makes AMI the preferred method for finding "air gaps" such as delamination, cracks, voids, and porosity. C-SAM analysis, which is a type of AMI, was widely used in the past for evaluation of plastic microelectronic circuits, especially for detecting delamination of direct die bonding. With the introduction of the flip-chip die attachment in a package; its use has been expanded to nondestructive characterization of the flip-chip solder bumps and underfill. Figure 1.1 compares visual and C-SAM inspection approaches for defect detection, especially for solder joint interconnections and hidden defects. C-SAM is specifically useful for package features like internal cracks and delamination. C-SAM not only allows for the visualization of the interior features, it has the ability to produce images on layer-by-layer basis. Visual inspection; however, is only superior to C-SAM for the exposed features including solder dewetting, microcracks, and contamination. Ideally, a combination of various inspection techniques - visual, optical and SEM microscopy, C-SAM, and X-ray - need to be performed in order to assure quality at part, package, and system levels. This reports presents evaluations performed on various advanced packages/assemblies, especially the flip-chip die version of ball grid array/column grid array (BGA/CGA) using C-SAM equipment. Both external and internal equipment was used for evaluation. The outside facility provided images of the key features that could be detected using the most advanced C-SAM equipment with a skilled operator. Investigation continued using in-house equipment with its limitations. For comparison, representative X-rays of the assemblies were also gathered to show key defect detection features of these non-destructive techniques. Key images gathered and compared are: Compared the images of 2D X-ray and C-SAM for a plastic LGA assembly showing features that could be detected by either NDE technique. For this specific case, X-ray was a clear winner. Evaluated flip-chip CGA and FCBGA assemblies with and without heat sink by C-SAM. Only the FCCGA package that had no heat sink could be fully analyzed for underfill and bump quality. Cross-sectional microscopy did not revealed peripheral delamination features detected by C-SAM. Analyzed a number of fine pitch PBGA assemblies by C-SAM. Even though the internal features of the package assemblies could be detected, C-SAM was unable to detect solder joint failure at either the package or board level. Twenty times touch ups by solder iron with 700degF tip temperature, each with about 5 second duration, did not induce defects to be detected by C-SAM images. Other techniques need to be considered to induce known defects for characterization. Given NASA's emphasis on the use of microelectronic packages and assemblies and quality assurance on workmanship defect detection, understanding key features of various inspection systems that detect defects in the early stages of package and assembly is critical to developing approaches that will minimize future failures. Additional specific, tailored non-destructive inspection approaches could enable low-risk insertion of these advanced electronic packages having hidden and fine features.
Single-Event Effects (SEE) testing was conducted on the AMD Ryzen 3 1200 microprocessor. Testing was conducted at Massachusetts General Hospital's (MGH) Francis H. Burr Proton Therapy Center on June 2nd, 2019.
Single-Event Effects (SEE) testing was conducted on the AMD Ryzen 3 2200G microprocessor with integrated graphics. Testing was conducted at Massachusetts General Hospital's (MGH) Francis H. Burr Proton Therapy Center on June 2nd, 2019.
Single-Event Effects (SEE) testing was conducted on the nVidia Jetson TX2 System on Chip (SOC). Testing was conducted at Massachusetts General Hospital's (MGH) Francis H. Burr Proton Therapy Center on June 2nd, 2019.
Many aspects of chip scale package (CSP) technology, with focus on assembly reliability characteristics, are being investigated by the JPL-led consortia. Three types of test vehicles were considered for evaluation and currently two configurations have been built to optimize attachment processes.
This paper reviews many factors that affect interconnect reliability of commercial-off-the-shelf (COSTS) chip scale package (CSP) assemblies.
A roadmap giving technology forecasts and recommendations for research direction for advanced electronic interconnection technology for space applications is presented.