Ceramic thermal wind sensor based on advanced direct chip attaching package

An advanced direct chip attaching packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct chip attaching （DCA） packaging is adopted and this new packaged method simplifies the processes of packaging further. Simulations of the advanced DCA packaged sensor based on computational fluid dynamics （CFD） model show the sensor can detect wind speed and direction effectively. The wind tunnel testing results show the advanced DCA packaged sensor can detect the wind direction from 0° to 360° and wind speed from 0 to 20 m/s with the error less than 0.5 m/s. The nonlinear fitting based least square method in Matlab is used to analyze the performance of the sensor.

Co‑packaged optics(CPO):status,challenges,and solutions

Due to the rise of 5G,IoT,AI,and high-performance computing applications,datacenter trafc has grown at a compound annual growth rate of nearly 30%.Furthermore,nearly three-fourths of the datacenter trafc resides within datacenters.The conventional pluggable optics increases at a much slower rate than that of datacenter trafc.The gap between application requirements and the capability of conventional pluggable optics keeps increasing,a trend that is unsustainable.Copackaged optics(CPO)is a disruptive approach to increasing the interconnecting bandwidth density and energy efciency by dramatically shortening the electrical link length through advanced packaging and co-optimization of electronics and photonics.CPO is widely regarded as a promising solution for future datacenter interconnections,and silicon platform is the most promising platform for large-scale integration.Leading international companies(e.g.,Intel,Broadcom and IBM)have heavily investigated in CPO technology,an inter-disciplinary research feld that involves photonic devices,integrated circuits design,packaging,photonic device modeling,electronic-photonic co-simulation,applications,and standardization.This review aims to provide the readers a comprehensive overview of the state-of-the-art progress of CPO in silicon platform,identify the key challenges,and point out the potential solutions,hoping to encourage collaboration between diferent research felds to accelerate the development of CPO technology.

Low Dielectric Benzocyclobutene-type Polymers Based on Facile Synthesis of Linear Fluorinated Monomer

A linear fluorinated benzocyclobutene-type monomer(4F-bis-BCB) was facilely synthesized by a one-step copper-catalyzed etherification reaction and a simple precipitation post-purification method.Moreover,a series of BCB-based polymeric low-dielectric(low-k)materials were obtained by the thermal-induced ring-opening copolymerization of 4F-bis-BCB with divinyl tetramethyl disiloxanebisbenzocyclobutene(DVS-BCB) monomer and further simple thermal curing at high temperature(200-300℃).The resultant fully cured materials demonstrated excellent low dielectric properties at high frequency of 10 GHz(dielectric constant(D_(k))<2.6,dielectric loss(D_(f))<1.57×10^(-2)),great hydrophobicity(water contact angle>116°),ultra-low water absorption(<0.19% after soaked in water at room temperature for 60 h) and excellent planarization ability(surface roughness<0.56 nm of 3 μm-thick film).Overall,this new fluorinated BCB-type monomer provides us an alternative for the facile preparation of low-k polymeric materials and exhibits great potential for future applications in high-frequency communication and three-dimensional high-density packaging technologies.