Wan Mokhdzani Wan Norhaimi

Wire Bond Shear Test Simulation on Hemispherical Surface Bond Pad

Wire bonding process is an interconnection method adopted in the semiconductor packaging manufactory. One of the method used to assess the reliability and bond strength of the bonded wires are wire bond shear test .In this study, simulation on wire bond shear test is done to evaluate the stress response of the bonded wire when sheared on a hemispherical surface bond pad. The contrast between three types of wire material:gold(Au), aluminum(Al) and copper(Cu) were carry out to examine the effects of wire material on the stress response of bonded wire during wire bond shear test. The simulation results showed that copper wire bond induces highest stress and gold wire exhibits the least stress response.

Shear Ram Speed Characterization for Copper Wire Bond Shear Test

This paper presents the evaluation of the stress and strain response of the copper ball bond during wire bond shear test using finite element analysis. A 3D non-linear finite element model was developed for the simulation. The effects of the shear ram speed on the stress and strain response of the copper ball bond were investigated. A preliminary investigation confirms that shear ram speed has a significant effect on the von mises stress and equivalent strain response of the copper ball bond during wire bond shear test

Surface variation analysis of proximal interphalangeal joint of osteoarthritis with fringe projection profilometry

The proximal interphalangeal joint (PIP) is the most important joint of the finger and is one of the most common joints to be affected by hand osteoarthritis (OA) due to excessive usage of the hand. PIP injury which may lead to osteoarthritis occurs when the protective cartilage on the boundaries of the joint begins to wear off or simply by a hyperextension of the joint. Currently, in order to diagnose joint deformity of the hand OA, particular imaging modalities namely the X-ray scanning and magnetic resonance imaging (MRI) is used but has its limitations such as radiation concerns and can be quite expensive. In this work, a fringe projection profilometry system which comprises of an LCD projector, CCD camera, and a personal computer has been developed to analyze surface changes of the PIP joint. The central concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted using the 3 steps 2 shift method for obtaining the phase map image. Grayscale analysis and pixel tracing were applied to detect the deformation of the PIP joint on a live individual. The result has demonstrated a successful method of PIP joint deformation detection based on the pixel tracking differences of a static and deformed state of the PIP joint.

Breast surface coordinate variation analysis caused by round shape tumor with fringe projection profilometry

Breast cancer is one of the fatal diseases and is one of the leading causes of death among women. Early screening for breast cancer is highly needed among women. Monitoring of the disease is also extremely vital for determining the best possible method of treatment. One of the most common symptoms of breast cancer is the breast surface change caused by the tumor within the breast. Shapes of the tumor vary among the patients, and some of the standard shapes of the tumor are round, oval, irregular, spiculated and microlobulated. Current common imaging modalities of diagnosing for breast tumor is the Magnetic Resonance Imaging (MRI), ultrasound and mammography. The current imaging modalities have been known to diagnose the disease but also has its limitations due to exposure concerns. In this work, the changes of breast surface are analyzed using a proposed fringe projection imaging modality. Surface changes of the breast were analyzed with the presence of a round shape tumor varied from 0.5 cm to 2 cm. The fringe projection profilometry system has successfully demonstrated its ability in detecting the pixel coordinate changes of the breast surface caused by the size variation of the tumor.

Fringe visibility analysis on silica glass based on automated Michelson interferometry system

A non-contact measurement method based on fringes produced from Michelson interferometry for fringe visibility analysis of transparent silica (SiO2) glass has been developed. An automatic micro-controlled stepper motor is implemented on the Michelson Interferometer to provide small micro displacement on the movable mirror and enable fringe shift. Through fringe visibility measurement, fringe shifting through micro-controlled stepper motor allows consistent and precise measurement. Analysis of fringe visibility was conducted on several samples etched with Hydrofluoric (HF) acid. The main fringe visibilities obtained after the silica glass were etched with HF ranged from 0.67-0.73. Fringe visibility of the silica glass samples increased when the time of etching of HF was reduced. Based on the results obtained the automatic fringe shift with micro-controlled stepper motor reduced human error and has better resolution in intensity measurement which allows fringe visibility to be measured more accurately. The fringe visibility analysis can also assist in surface profiling of other transparent and reflective thin films.

Hydrophilicity Characterization on Cleaned Bonded Silicon Based Surface

This paper reports on the contact angle measurement analysis on a silicon based surface for anodic bonding process cleaned by three distinct cleaning processes. The three cleaning solutions tested in this experiment were RCA, piranha and acetone. Water Droplet Test (WDT) was done to analyze the contact angle of micro droplet on sample surface. It can be done by dropping a droplet of water in constant volume at the fixed height and angle. Only RCA process constantly decreases the contact angle value after cleaning. The compilations of data strongly proved that all samples become hydrophilic after RCA cleaning process. Samples which undergo piranha and acetone cleaning did not prove any characteristic of hydrophilic or hydrophobic surface after cleaning.

Contact Angle Analysis on Glass Based Surface

This paper reports on the contact angle measurement analysis on a glass based surface for anodic bonding process cleaned by three distinct cleaning processes. The three types of glass based surface used were silica, pyrex, and soda lime glass. The three cleaning solutions tested in this experiment were RCA, piranha and acetone. Water Droplet Test (WDT) was done to analyze the contact angle of micro droplet on sample surface. It can be done by dropping a droplet of water in constant volume at the fixed height and angle. Only RCA process constantly decreases the contact angle value after cleaning. The compilations of data strongly proved that all samples become hydrophilic after RCA cleaning process. The solid surface is considered hydrophilic when water contact angle is smaller than 90°, and hydrophobic profile if the water contact angle is larger than 90°. Samples which undergo piranha and acetone cleaning did not prove any characteristic of hydrophilic or hydrophobic surface after cleaning.

Bond Strength Comparison between Silicon and Glass Based Surface Using Anodic Bonding

This paper reports on the bond strength comparison between silicon and different glass based materials via anodic bonding approach. The three types of glass based surface used were silica, pyrex, and soda lime glass. Silicon will be placed on the positive terminal and glass based materials will be placed on the negative terminal. Experiments were carried out using an in-house designed anodic bonder and the bond strength were measured using a bond strength tester. The anodic bonding approach process was done in two sets which are before and after the cleaning process for each sample. For every set, there are three different bonding partners, which are silicon with silica, silicon with Pyrex, and silicon with soda lime glass. From the results, it can be seen that almost all samples showed higher bond strength after the cleaning process. Silicon with soda lime glass bonding shows the highest bond strength compared with other materials.

Design, Simulation and Characterization of Moly Permalloy Based Electromagnetic Sensor

In this paper it is shown the design, simulation and characterization of Moly Permalloy based electromagnetic sensor in MEMS software. The dimension of the device is minimized to the smallest the software can simulate which is 1 micron. Total of 9 models had been simulated which differs in thickness of the material and designs. A new design was created to compare the results with the existing designs. The creation of the new design has given better results than the existing designs in terms of the current flow and the magnetic induction.