Three-dimensional simulation of fabrication process-dependent effects on single event effects of SiGe heterojunction bipolar transistor

The fabrication process dependent effects on single event effects （SEEs） are investigated in a commercial silicon- germanium heterojunction bipolar transistor （SiGe HBT） using three-dimensional （3D） TCAD simulations. The influences of device structure and doping concentration on SEEs are discussed via analysis of current transient and charge collection induced by ions strike. The results show that the SEEs representation of current transient is different from representation of the charge collection for the same process parameters. To be specific, the area of C/S junction is the key parameter that affects charge collection of SEE. Both current transient and charge collection are dependent on the doping of collector and substrate. The base doping slightly influences transient currents of base, emitter, and collector terminals. However, the SEEs of SiGe HBT are hardly affected by the doping of epitaxial base and the content of Ge.

Principle and Process Window of Cerium Dioxide Thin Film Fabrication with Dual Plasma Deposition

Cerium dioxide, CeO2, is a potentially superior material in a myriad of areas, and many methods have been proposed to deposit single crystal CeO2 thin films. A novel fabrication technique utilizing dual plasma generated by metal vacuum arc (MEVVA) and radio frequency (RF) is discussed in this paper. We have recently conducted a systematic investigation to determine the optimal process window to deposit CeO2 thin films'on Si(100) substrates. The X-ray diffraction results show the existence of CeO2(100) in the as-deposited sample.

Design and manufacturing of soft electronics for in situ biochemical sensing

Soft(flexible and stretchable) biosensors have great potential in real-time and continuous health monitoring of various physiological factors, mainly due to their better conformability to soft human tissues and organs, which maximizes data fidelity and minimizes biological interference.Most of the early soft sensors focused on sensing physical signals. Recently, it is becoming a trend that novel soft sensors are developed to sense and monitor biochemical signals in situ in real biological environments, thus providing much more meaningful data for studying fundamental biology and diagnosing diverse health conditions. This is essential to decentralize the healthcare resources towards predictive medicine and better disease management. To meet the requirements of mechanical softness and complex biosensing, unconventional materials, and manufacturing process are demanded in developing biosensors. In this review, we summarize the fundamental approaches and the latest and representative design and fabrication to engineer soft electronics(flexible and stretchable) for wearable and implantable biochemical sensing. We will review the rational design and ingenious integration of stretchable materials, structures, and signal transducers in different application scenarios to fabricate high-performance soft biosensors. Focus is also given to how these novel biosensors can be integrated into diverse important physiological environments and scenarios in situ, such as sweat analysis, wound monitoring, and neurochemical sensing. We also rethink and discuss the current limitations,challenges, and prospects of soft biosensors. This review holds significant importance for researchers and engineers, as it assists in comprehending the overarching trends and pivotal issues within the realm of designing and manufacturing soft electronics for biochemical sensing.

Fabrication,microstructure and mechanical properties of Mg matrix composites reinforced by high volume fraction of sphere TC4 particles

A novel liquid settling method was investigated and applied to fabricate TC4 spherical particle reinforced AZ91 alloy matrix composites.This method was called liquid state settling technique in which TC4 particles would settle down under the force of gravity.High volume fraction(50%)particle reinforced AZ91 composites could be easily obtained via this novel method.This is difficult to achieve for other traditional liquid fabrication methods.In addition,there was a good dispersion of TC4 particles in the AZ91 matrix and no clusters were found,which indicate that this method was feasible.Interfacial reaction occurred and the reaction product was confirmed to be Al2Ti.Three kinds of pre-dispersion technologies were used before the settling process and different interfacial microstructures were found.Theoretical calculation and experimental results both indicated that the interfacial product which was embedded in the matrix strengthened the composites and improved the tensile strength.

Solid oxide fuel cell:materials,technology and application

Solid oxide fuel cells (SOFCs) offer a clean, pollution-free technology for the electrochemical conversion of chemical energy of hydrocarbon fuels into electricity. Many programs are being initiated in the United States, Europe, Japan and so on. The funding for SOFC development worldwide has risen dramatically and this trend is expected to continue for at least the next decades. These development programs are also investigating wider applications of SOFCs in stationary, residential, transportation and military sectors. Finally, it is summarized the key materials and fabrication processes of SOFC in this paper.

Implementation of Pre-Heating System in Stenters for Improving Machine Performance and Increasing Efficiency

In textile finishing, stenters always draw considerable attention to newer inventions to boost up production via maximum utilization of energy. Prior to main drying or heat-setting chambers, intermediate heating of cylindrical system especially by steam has a direct blessing to moisture evaporation, processing speed, fabric quality and so on. Based on actual operational data, this study reveals the outcomes of a pre-heating module installed within a stenter. After employing the pre-heating system to knit fabrics of different structures and compositions, 23% - 61% moisture reduction was found and the speed of processing fabrics was increased simultaneously by 17% - 30% without any compromise on fabric quality. Moreover, no less than 8.21% savings in annual electricity consumption were observed.

Integrated fabrication process with multiple optimized factors for high power density of IPMC actuator

Ionic polymer-metal composites(IPMCs)are typical smart mate-rials that are commonly used in bionic applications,including soft robots,bionic flapping aircraft,and bionic fish.However,their low output force seriously limits device performance.Stacking of multiple IPMC actuators to improve the overall performance of soft actuators is a strategy that is used in practical applications.Under the energy dissipation condition in the IPMC stacking structure,if each single IPMC in the struc-ture has high power density,the structure will produce excel-lent performance with high efficiency that can greatly promote wider application of IPMC actuators.To meet this requirement,a method for fabrication process integration with multiple opti-mized factors was used to obtain IPMC materials in this paper.Carbon nanotube(CNT)doping,isopropyl alcohol-assisted plat-ing,and hot pressing with a mesoscopic structural mold were selected as typical optimization methods for process integration and were initially investigated separately to determine the opti-mal process parameters.By combining the best process para-meters in an integrated process,the IPMC treated by isopropyl alcohol-assisted plating and CNT doping process(No.AC7)showed excellent actuation performance and high work density(~9.71/12.36 gf,~14.93/31.89 kJ/m^(3) under 3/4 VDC).The enhanced performance meets the requirements for practical bionic applications.

Fabrication techniques and applications of flexible graphene-based electronic devices

In recent years, flexible electronic devices have become a hot topic of scientific research. These flexible devices are the basis of flexible circuits, flexible batteries, flexible displays and electronic skins. Graphene-based materials are very promising for flexible electronic devices, due to their high mobility, high elasticity, a tunable band gap, quantum electronic transport and high mechanical strength. In this article, we review the recent progress of the fabrication process and the applications of graphene-based electronic devices, including thermal acoustic devices, thermal rectifiers, graphene-based nanogenerators, pressure sensors and graphene-based light-emitting diodes. In summary, although there are still a lot of challenges needing to be solved, graphene-based materials are very promising for various flexible device applications in the future.

Fabrication-constrained inverse design and demonstration of high-performance grating couplers

A high-performance grating coupler(GC) operating at a wavelength of 1550 nm is proposed by utilizing the adjoint-based inverse design algorithm on a 220 nm silicon-on-insulator(SOI) substrate. The grating scheme offers several advantages,including simple structure, large minimum feature size(MFS), manufacturing friendliness, support for large-scale production and multi-project wafer (MPW) runs, etc., while simultaneously maintaining exceptional coupling performance and fabrication tolerance. The design process incorporates various fabrication constraints to satisfy the specifications of different foundry processes. The optimized GC demonstrates excellent coupling performance and 3 d B bandwidth within the MFS range of 60 to 180 nm. The simulated coupling efficiency(CE) of the GC with 130 nm MFS is-1.69 dB, whereas the experimentally measured CE of the fabricated GC using electron beam lithography(EBL) is-2.83 dB. Notably, the experimental CE of the GC with 180 nm MFS fabricated using 248 nm deep ultraviolet(DUV) lithography is-2.77 dB, representing the highest experimental CE ever reported for a single-layer etching C-Band GC supported by MPW runs fabricated on 220 nm SOI without utilizing any back reflector, multi-etch layer, or overlay. The manufacturing outcomes of the same GC structure employing different manufacturing processes are discussed and analyzed, providing valuable insights for the fabrication of silicon photonics devices.