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In this paper, firstly, the precise lead frame LED module is built with the help of 3D microscopy. Secondly, the micro stamping technological parameters and processing steps are analyzed according to the actual production. With the information obtained, the micro stamping processing is simulated by non-linear FEA software ABAQUS, which focuses on angle deflection of lens in the process of micro stamping...
Reliability is essential for large-scale applications of high-power light-emitting diode (LED) devices, modules, and systems for general illumination. In this paper, the reliability of a novel application-specific LED package (ASLP) is investigated by thermal shock testing, failure analysis, and fluid–solid coupling thermo-mechanical simulation. The reliability of the ASLP modules was validated with...
As a newly lighting source, high power white light emitting diodes (LEDs) have many excellent performances and begin to be widely used. The LED street light fixture is one of the most typical and popular applications, which is studied and developed worldwide. However, those studies mainly focused on its light efficiency, light pattern, color temperature, and so on, few concentrated on the reliability...
The heteroepitaxial growth of GaN-based epitaxial layers on sapphire and SiC substrates increases process complexity during light-emitting diodes (LEDs) manufacturing process. The large lattice mismatch and coefficient of thermal expansion (CTE) mismatch between substrate materials and GaN materials, resulting in wafer curvature issue which can impact wavelength and intensity uniformity. Obtaining...
High junction temperature accelerates the degradation of the chips and the package materials of high power light emitting diodes (LEDs). In this paper, two experiments were conducted to investigate the fluctuation of junction temperature in the aging process. At the ambient temperature of 65°C, the samples from four different types of LED packages were used to investigate the variation of junction...
GaN thin film grown on sapphire substrate of 50 mm*50 mm in size are successfully bonded and transferred onto Si substrate using Au-Sn wafer bonding followed by grinding, chemical mechanical polishing (CMP) and dry etching. The GaN/sapphire structures are integrated to receptor Si substrate by thermal pressure bonding process. The bonding medium comprises Au-Sn multilayer composite deposited directly...
In this paper, the wire bonding process of high power light emitting diodes (LED), which was simplified to consist of impact and vibration stages, was investigated by using a nonlinear finite element method. Parametric studies were carried out to examine the effects of the ultrasonic vibration amplitude, the friction coefficient between the free air ball (FAB) and bond pad, the incline of LED chip...
Undesired residual strain always exists in the epitaxial film inevitably as a result of lattice mismatch and thermal expansion mismatch between the substrate and the epitaxial film. The strain affects crystalline quality as well as optical and electrical properties of LED epitaxial film. In this paper, we report on the effects of strain on the emission properties of III-nitrides based LEDs grown on...
Multi-physics multi-scale modeling issues in various stages of the LED manufacturing, 3D-SiP, and nano interconnects have been discussed. Molecular dynamics (MD) and finite element method (FEM) have been used to study the scale effect of the material properties and the prediction of the module behaviors which are critical to LED fabrication. We propose a new concept to integrate multi-physics/multi-scale...
A multi-physics multi-scale modeling platform has been developed and it has been applied to various stages of the LED manufacturing such as MOCVD reactor design, epitaxial growth based on silicon wafer, chip design and manufacturing, module packaging and assembly, and specific lamps. Discussions are also given to the ultra-scalable reactor design, material constitutive modeling, and curvature evolution...
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