This book aims to provide a comprehensive reference into the critical subject of failure and degradation in organic materials, used in optoelectronics and microelectronics systems and devices. Readers in different industrial sectors, including microelectronics, automotive, lighting, oil/gas, and petrochemical will benefit from this book. Several case studies and examples are discussed, which readers will find useful to assess and mitigate similar failure cases. More importantly, this book presents methodologies and useful approaches in analyzing a failure and in relating a failure to the reliability of materials and systems.

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This book describes for readers various technical outcomes from the EU-project IoSense. The authors discuss sensor integration, including LEDs, dust sensors, LIDAR for automotive driving and 8 more, demonstrating their use in simulations for the design and fabrication of sensor systems. Readers will benefit from the coverage of topics such as sensor technologies for both discrete and integrated innovative sensor devices, suitable for high volume production, electrical, mechanical, security and software resources for integration of sensor system components into IoT systems and IoT-enabling systems, and IoT sensor system reliability.




Describes from component to system level simulation, how to use the available simulation techniques for reaching a proper design with good performance;
Explains how to use simulation techniques such as Finite Elements, Multi-body, Dynamic, stochastics and many more in the virtual design of sensor systems;
Demonstrates the integration of several sensor solutions (thermal, dust, occupancy, distance, awareness and more) into large-scale system solutions in several industrial domains (Lighting, automotive, transport and more);
Includes state-of-the-art simulation techniques, both multi-scale and multi-physics, for use in the electronic industry.
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In the past four years we have witnessed rapid development in technology and significant market penetration in many applications for LED systems. New processes and new materials have been introduced; new standards and new testing methods have been developed; new driver, control and sensing technologies have been integrated; and new and unknown failure modes have also been presented. In this book, Solid State Lighting Reliability Part 2, we invited the experts from industry and academia to present the latest developments and findings in the LED system reliability arena. Topics in this book cover the early failures and critical steps in LED manufacturing; advances in reliability testing and standards; quality of colour and colour stability; degradation of optical materials and the associated chromaticity maintenance; characterization of thermal interfaces; LED solder joint testing and prediction; common failure modes in LED drivers; root causes for lumen depreciation; corrosion sensitivity of LED packages; reliability management for automotive LEDs, and lightning effects on LEDs.
This book is a continuation of Solid State Lighting Reliability: Components to Systems (published in 2013), which covers reliability aspects ranging from the LED to the total luminaire or system of luminaires. Together, these two books are a full set of reference books for Solid State Lighting reliability from the performance of the (sub-) components to the total system, regardless its complexity. @en

Commercial claims for LED-based products in terms of lumen maintenance are fully based on TM-21 extrapolations using LM-80 data. This chapter indicates that there may be a risk in doing this as TM-21 only relies on the behavior of the average LED degradation, instead of taking into account the degradation of all individual LEDs. Therefore, we propose a more profound statistical approach in order to make the appropriate step from TM-21 extrapolation to lumen maintenance on a product level. This is needed as some commercial claims are based on 10 years of warranty and some service bids provide periods of 20–25 years of operation. This chapter reviews the different approaches currently available to perform lumen maintenance extrapolations.@en

Color stability is of major concern for LED-based products. Currently, much effort is done on lumen maintenance, and for color shift, no agreed method currently exists, be it from testing or from prediction side. To investigate the physics of color shift, we present experiments of each individual part failure of each individual part that are present in LED-based products. In order to develop a color shift prediction method, it is imperative to investigate the color shift contribution by each individual part. We present a new method to predict color shift on a system level, which we named the view factor approach. We compare this prediction method with experiments on luminaire level to conclude that we have taken satisfactory first steps in the field of color shift predictions for LED-based systems.@en

The penetration of solid state lighting applications is due to the promise of a low-cost reliable solution by means of application of low- and mid-power LEDs. These LED packages are manufactured by making use of new processes and materials which in principle introduces a series of known and unknown failure modes. Corrosion is a specific failure mode which limits the lifetime, and hence manufacturers realize that their package integrity needs to be improved. This chapter describes the sensitivity to corrosion of LED packages. In the first part, an introduction to chemical incompatibility is given. In the second part, different sources of corrosion are distinguished. The construction of LED packages and their vulnerability to corrosion is described in the third part. In the fourth part of this chapter, testing methods are reviewed and their effectiveness to simulate real-life conditions. A series of experimental setups is used to explore the behavior of LED packages in contaminated environments. A combined experimental–theoretical approach is used to describe the performance in certain conditions of pollution. This will be covered in the fifth part. The last part describes a list of classes of chemicals, often found in electronics and construction materials for luminaires that may affect LED performance and for this reason should be avoided for the design of SSL solutions.@en

This chapter investigates the reliability of the integrated LED lamps with electrolytic capacitor-less LED drivers. Firstly, the impact of the interaction between the degradations of the LED light source and the driver on the lumen depreciation is studied. The electronic-thermal simulation was carried out to obtain the history of temperatures of LED and driver, the driver’s output current, and the luminous flux considering the variations of temperature and current throughout the operation life. It is found that the ultimate lamp’s lifetime is significantly less than the individual lifetimes of the preselected LED and driver. It is concluded that it is necessary to apply the electronic-thermal simulations to predict the lifetime of LED lamps when driver’s lifetime is comparable to the LED’s lifetime. Secondly, this chapter focuses on predicting the catastrophic failure of an electrolytic capacitor-free LED driver during the lumen depreciation process. Electronic-thermal simulations are utilized to obtain the lamp’s dynamic history of temperature and electrical current for two distinct modes: constant current mode (CCM) and the constant optical output (CLO) mode, respectively. A fault tree method is applied to calculate the system’s MTTF, and the LED’s lifetime also is calculated. The CLO mode increases the LED’s current exponentially to maintain the constant light output. As a result, junction temperatures of LEDs, MOSFET, and diode rise significantly, leading a shorter lifetime and MTTF. Compare with the current of the MOSFET, the increased junction temperature has larger effects on the failure rate. The MOSFET contributes more to the driver’s failure rate than the diode. For the CCM mode, junction temperatures increase slightly and have a little shorter lifetime and MTTF.@en

Traditional lighting is focused on the prevention of hardware failures. With the trend toward controlled and connected systems, other components will start playing an equal role in the reliability of it. Here reliability need to be replaced by availability, and other modeling approaches are to be taken into account. Software reliability can only be covered by growth models, with the Goel-Okumoto as a promising candidate. System prognostics and health management is the next step to service the connected complex systems in the most effective way possible. In this chapter we highlight the next frontiers that will need to be taken in order to move the traditional lighting catastrophic failure thinking into a thinking more toward new ways how system (degraded) functions can fail or be compromised.@en

Solid State Lighting Reliability: Components to Systems begins with an explanation of the major benefits of solid state lighting (SSL) when compared to conventional lighting systems including but not limited to long useful lifetimes of 50,000 (or more) hours and high efficacy. When designing effective devices that take advantage of SSL capabilities the reliability of internal components (optics, drive electronics, controls, thermal design) take on critical importance. As such a detailed discussion of reliability from performance at the device level to sub components is included as well as the integrated systems of SSL modules, lamps and luminaires including various failure modes, reliability testing and reliability performance.

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