Realizing a convenient way to control the phonon laser action is of great importance and may find applications in phonon laser devices engineering. Here we propose a vector parity time (PT)-symmetric optomechanical system to study the phonon laser action. We find that there is a specific region for the optimum mechanical gain appearing in parameter areas of the cavity gain and loss. The intensity of phonon laser action can be well controlled by adjusting the polarization of the pump field. The threshold value of phonon laser action manifests as a function relationship of the polarization direction θ. Furthermore, an ultralow threshold (even if threshold less) can be obtained around the exceptional point with the gain-loss balance. Our results indicate that the intensity and threshold of the phonon laser action can be continuously adjusted by only tuning the photon polarization, which provides a new degree of freedom to realize phonon laser regulation.

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The realization of vertical interconnected devices/chips using through silicon vias (TSVs) is one of the key emerging trends in 3D IC package. However, the new technology is in its R&D level and there are still many technical obstacles to overcome for it to be used for real products. For instance, some key technical challenges still exist in the TSV formation processes such as high aspect ratio via filling, wafer thinning and handling, etc. And the issue of reliability will become extraordinary crucial for TSV technology to be used in high volume production of electronic devices. The trial-and-error method is obviously not adaptable due to its time consuming and high cost due to the demanding pressure of time to market and time to profit. Therefore, there is an urgent need to develop innovative design methods for TSV/SiP based modules.In this paper, the efforts of the construction of an expert advisor for integrated virtual manufacturing and reliability design and evaluation for the TSV/SiP based modules are presented. Firstly, the material property database of TSV based package is built up through material property characterization by the submicron tester, dynamic mechanical analysis (DMA), thermal mechanical analysis (TMA) and nano-indentation. Secondly, novel modeling techniques for the copper electroplating, grinding and chemical mechanical planarization (CMP) and stacked bonding processes are developed for simulation of the whole manufacturing processes of TSV/SiP modules. Then the virtual prototyping method is used to validate and design the reliability of TSV/SiP modules such as stacked-dies packaging and hermetic MEMS packaging with the numerical simulation models of thermal cycling testing and electromigration testing. And finally the expert advisor for the TSV/SiP modules is integrated based on the results from the numerical modeling which are validated by the experiments. IntroductionThe realization of vertical interconnected devices/chips using through silicon vias is one of the key emerging trends in wafer level packaging (WLP), System in Package (SiP), and 3D IC package. This technology offers significant advantages in terms of electrical performances, e.g., signal transmission, interconnect density and reduced power consumption as well as form factor, heterogeneous integration, and manufacturing cost reduction. However, the TSV process is demonstrated at the R&D level [1] . The main processes of TSV are not mature yet and the cost is still high. The issue of reliability will become extraordinary crucial for this technology to be used in

We presented a method to control the intensity of a phonon-laser mode (the vibrational excitations of a mechanical mode) by adjusting the polarization of the pump light based on the experimentally achievable parameters, which provides an additional degree of freedom to control the phonon laser action. Due to orthogonally polarized modes of cavity, the polarization behavior of light field which describes it’s vector nature is introduced to control phonon laser action in our scheme. Compared with the traditional phonon laser scheme, polarization-related phonon laser in the coupled vector cavity optomechanics can be effectively controlled without changing other parameters of the device. This result provides an useful approach for acquiring polarization-related phonon laser by on-chip optical device.