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© 2015 Springer Science+Business Media New York Solid-state processes of bonding 1 mm copper (Cu) wires on Cu substrates and silicon (Si) chips, respectively, were developed. To overcome Cu oxidation issue, the bonding surface on the wire was plated a silver (Ag) layer. An annealing step followed to make the Ag layer much easier to deform and conform to the Cu or Si bonding surfaces. The bonding process was performed at 300 °C with 6.89 MPa. Wire-bond cross sections were studied using optical and electron microscopy, respectively. The images obtained exhibit nearly perfect Ag–Cu bonding interface. For wire-bonds made on Cu substrate, in-plane (shear) pull test measured a breaking of force 20.7–23.7 kg, comparable to the 22.5 kg breaking force of the Cu wire itself. Breaking forces on vertical (peel) pull test are about one-half of in-plane pull test results. For wire-bonds made on Si chip, breaking forces are about 80 % of those made on Cu substrate. Fracture modes were evaluated in details. 90 % of the wire-bonds broke with three modes mixed together: near Cu–Ag plating interface, inside Ag layer, and Ag–Cu bonding interface. Thus, the bonding interface is as strong as other regions of the wire-bond. This solid-state wire bonding process is expected to have valuable applications in high power and high temperature devices and modules where the wire-bonds have to stand alone without protection due to lack of high temperature molding compound and reinforcing materials.

Multiple forms of interference and noise that impact the receiver's capacity to receive and interpret satellite signals, and consequently the preciseness of positioning and navigation, may be present during the processing of Global Positioning System (GPS) navigation. The non-Gaussian noise predominates in the signal owing to the fluctuating character of both natural and artificial electromagnetic interference, and the algorithm based on the minimum mean-square error (MMSE) criterion performs well when assuming Gaussian noise, but drops when assuming non-Gaussian noise. The maximum correntropy criteria (MCC) adaptive filtering technique efficiently reduces pulse noise and has adequate performance in heavy-tailed noise, which addresses the issue of filter performance caused by the presence of non-Gaussian or heavy-tailed unusual noise values in the localizing measurement noise. The adaptive kernel bandwidth (AKB) technique employed in this paper applies the calculated adaptive variables to generate the kernel function matrix, in which the adaptive factor can modify the size of the kernel width across a reasonably appropriate spectrum, substituting the fixed kernel width for the conventional MCC to enhance the performance. The conventional maximum correntropy criterion-based extended Kalman filter (MCCEKF) algorithm's performance is significantly impacted by the value of the kernel width, and there are certain predetermined conditions in the selection based on experience. The MCCEKF with a fixed adaptive kernel bandwidth (MCCEKF-AKB) has several advantages due to its novel concept and computational simplicity, and gives a qualitative solution for the study of random structures for generalized noise. Additionally, it can effectively achieve the robust state estimation of outliers with anomalous values while guaranteeing the accuracy of the filtering. [ABSTRACT FROM AUTHOR]