Investigation of Adhesive’s Material in Hermetic MEMS Package for Interfacial Crack between the Silver Epoxy and the Metal Lid during the Precondition Test

A hermetic Micro-Electro-Mechanical Systems (MEMS) package with a metal lid is investigated to prevent lid-off failure and improve its reliability during the precondition test. While the MEMS package benefits from miniaturization and low cost, a hermetic version is highly sensitive to internal pressure caused by moisture penetration and the reflow process, thus affecting its reliability. In this research, the finite element method is applied to analyze the contact stress between the metal lid and the silver epoxy by applying the cohesive zone model (CZM). Moreover, the red dye penetration test is applied, revealing a microcrack at the metal lid/silver epoxy interface. Further analyses indicate that the crack is caused by internal pressure. According to the experimental testing and simulation results, the silver epoxy material, the curing process, the metal lid geometry, and the bonding layer contact area can enhance the bonding strength between the metal lid and the substrate.

ELASTİK MODÜL YAKLAŞIMI İLE SES HIZLARININ HESAPLANARAK TUNGSTENİN AKUSTİK EMPEDANS ÜZERİNDEKİ ETKİLERİNİN ARAŞTIRILMASI

Some metal filler powders, such as tungsten, are available as support materials in the bodies of ultrasonic transducers. The backing materials consist of two types of epoxy material, mainly hardener and adhesive, and filler powders. One of the reasons why these filler powders are incorporated into epoxy materials is the desire to achieve high acoustic impedance in ultrasonic probes. In this context, samples with different epoxy mixing ratios of tungsten added in amounts of 1, 2, 5 and 10 grams were prepared for the measurement, and the sound velocities used in the calculation of acoustic impedance were calculated over elastic modulus and densities measured by mechanical method. Thus, the effects of tungsten used in the support material in the probes of ultrasound devices were investigated. As a result, the increasing effect of tungsten on acoustic impedance was also determined with the calculations made by mechanical method.

Antenna Design and Fabrication with Circular Microstrip Patch: A Review

The paper presents a review on antenna designing and fabrication techniques with Microstrip Patch (MSP) development. The requirements of MSP are remote controlling, mobile communication, space communication and all wireless communication areas. Aim of this development is to provide a new approach of the designing and simulation of circularMSP for 5.8 GHz operating frequency. CST MICROWAVE STUDIO (MWS) facilitates the quick and accurate analysis of high frequency (HF) antennas which gives the responses and results before fabrication of actual patch with complete technology for 3D EM. FR-4 glass epoxy material board is used for fabrication which is admired and adaptable highpressure thermoset plastic laminate grade with superior strength to weight ratios. Circular MSP is easy to fabricate, portable, lightweight and low cost antenna. N9923A Field Fox RF VNA (Vector Network Analyser) were used for studying and testing all the parameters of fabricated MSP.

Silicon Die with Integrated Epoxy for Improved Interface Adhesion

Breakthroughs and innovations are constantly being developed in electronic packaging industry to address the manufacturing challenges and overcome existing assembly limitations. An augmented design of thin Silicon die is introduced to establish a robust and improved interface adhesion between the die and the die attach material during the die attach process. The wafer preparation flow is also presented. The realization of the augmented die design with integrated epoxy material would ultimately provide a robust connection and would mitigate the die attach related issues such delamination, die cracks and voids.

Die Attach Process Robustness through Epoxy Pattern Optimization for DFN Device

As the modern world evolves through innovation and technology, manufacturing companies of semiconductor drive their people to dedicate themselves on continuous improvement and technical advancement. Products they produce becomes smaller and thinner, but applications are limitless and innovative. In manufacturing of quad flat no lead packages, challenges were encountered during the die attach process especially in small die size. Die attach material overflow on pad is one of these, and certain parameters and techniques are explored to have a quality and robust process. Defining appropriate epoxy pattern with respect to the die size is a big factor to make sure no epoxy material will flow outside the die pad perimeter that may cause unit rejection. This paper will discuss the related issues of the said package by performing experiments and applying certain techniques to address the problem.

Roger 3450 Vs RF4 Martials - Based Frequency And Pattern Reconfigurable Rectangular Patch Slot Antennas For RFID Applications

Rectangular Patch Slot Antennas RPSA are getting becoming more likable and popular for practice in wireless implementations such as RFID applications especially in the UHF band thanks to its low-profile structure. This kind of antenna is able to deliver large communication distances but this antenna coverage is very weak which is part of the main drawbacks of these antennas. In this paper, Rectangular Patch Slot Antenna RPSA with different slots has been designed and simulated to be suitable for RFID applications. Circular polarized CP antenna that has been designed to use feed structure with vertical ground encircling a radiating component. The feeding method to feed this antenna is coaxial probe. The paper will concentration on both substrate materials Roger 4350 and FR4 Glass-Epoxy material to model and simulate the designs. The other factor of the design is the patch antenna will cut at the four truncated corners to enhance the antenna gain which will affect considerably the operating frequency. This paper aims to show and find the best feed point area that has an exceptional antenna return loss (S11) and high gain. S11 describe the power reflected from the antenna, which is known as the reflection coefficient S11 must be ≤ -10dB. The design and simulation results of RPSA has been done by high frequency simulation system (HFSS 13.0).

Addressing Delamination through Advanced Semiconductor Die Design

Innovations and breakthroughs are continuously driven in semiconductor manufacturing to overcome existing assembly limitations and recurring difficulties. This paper is focused on the resolution of the delamination issue during die attach assembly process. A new design of semiconductor die is presented to establish a robust adhesion or interface bonding between the silicon die and the epoxy material for die attach. The paper also provides the specialized design of manufacturing flow for the improved die design through advanced wafer fabrication method and wafer cutting technique. The realization of the advanced silicon die design would ultimately mitigate the delamination issue and would contribute for a robust die attach assembly process.

Hybridization Effect on Crashworthiness Parameters of Natural Composite

The use of metallic materials in automotive industry leads to increasing fuel consumption and cost, so trends are starting to use lighter and cheaper materials. In automotive applications, fibers are used in composites because they are stronger, stiffer, and lighter than bulk materials, and they can achieve higher energy absorbing compared to metallic materials. The purpose of this work is to study the potential utilization of natural fibers in the crash energy absorbing applications. The experimental procedures (the principle of a combination of manual layup and vacuum bladder technique) were applied to search the influence of utilizing jute fiber mat on crashworthiness parameters of composite materials with other kinds of fibers such as woven glass fiber reinforced epoxy composites. The study involved corrugated composite tubes with three layers of jute and hybrid glass-jute/epoxy material have been tested in uniaxial quasi-static crush conditions at the speed 10 mm/min. The results exhibit that the tube of jute fiber was somewhat lower than synthetic fibers, but the substitution of one layer of jute fiber with one layer of glass fiber resulted in an improvement in the crashworthiness parameters. As hybrid jute-glass was used, the best result was obtained, where energy absorption and specific energy absorption are improved by 17.75% and 25.122%, respectively.