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To promote the development of the solid state lighting and display industry, exploring excellent inorganic phosphors has always been a hot scientific and applied issue. Herein, we have constructed a series of Sm 3+activated La 7 O 6 (BO 3 )(PO 4 ) 2 (abbreviated as LBPO) phosphors by means of the short-time high-temperature solid phase synthesis process. The crystalline phase composition, micromorphology feature, ionic states of elements, and diffuse reflectance absorption performance were solved in detail. LBPO is suitable as phosphor host materials according to the investigation on electronic properties by density functional theory. The excitation and emission performance is significantly influenced by the crystalline structure of the LBPO host and doped Sm 3+ concentration. The optimized photoluminescence strategy is presented: upon the strongest near-ultraviolet (UV) excitation of 404 nm, LBPO:7% Sm 3+ displays intense orange-red visible luminescence with the dominant emission at 605 nm ( 4 G 5/2 → 6 H 7/2 of trivalent samarium). Its concentration quenching mechanism is the dipolar interaction. On the basis of the investigation of the detailed CIE chromaticity coordinate, color purity (CP), correlated color temperature (CCT), and internal quantum efficiency (IQE), we may use LBPO:Sm 3+ micropowder as an alternative ingredient for phosphor-converted near-UV-based warm white LEDs.

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Delamination was a critical failure to the microelectronics products, and it was introduced mainly by two factors: strong interface stress or poor interface adhesion. In this paper a tracking experiment confirmed the delamination between die attach and leadframe flag in a SOIC device, which occurred during wire bonding. Results of actual experiments and FEA found during the process flow, there were changes of structure profile as well as von Mises stress at the edge of die attach layer. This alternating stress was introduced by temperature cycling during D/A curing, wire bonding and following cooling; and resulted into the delamination at the interface, whose occurrence could be reduced when a higher peak temperature of D/A curing, a lower temperature of wire bonding, a thicker BLT or a CTE-lower die attach was applied. With a balance between delamination and other items, a final solution was proposed and got perfect results. InformationDue to the demands of higher integration level, higher power and lower cost in electronics industry, packaging technology and materials faced more and more challenges. Delamination was one common and critical failure, which may bring great destroys to the package [1-5]; such as die crack, wire bond lift or break, thermal and electrical performance degradation. If all interfaces in the package had perfect adhesions and the stresses were small, delamination was unlikely to occur. However, CTE mismatches between material couples, improper package structures, un-optimized process settings and extreme application environment with humidity or temperature cycling may result into strong interface stresses and package delamination [5][6][7][8][9][10][11][12][13].Some researchers used the method of finite element analysis (FEA) to predict the occurrence of delamination under different conditions. Interface shear stress or strain, von Mises stress, J-integrate and energy release rate were usual indicators to assess the delamination [5,[7][8][9][10][11]14]. While there were few papers about the effects of processes prior to molding on package delamination. This paper focused on the package delamination occurring before molding at the interface between die attach and leadframe flag. The results of actual experiments and FEA found the alternating interface stress, introduced by CTE mismatch and temperature cycling prior to molding, resulted into this delamination. At the same time, effects of some process factors were studied and a final solution was proposed to solve this delamination. BackgroundDuring the characterization of one small outline 28ld non exposed pad device, the package delamination between die attach and leadframe flag was found with through-scan CSAM