Moganraj Palianysamy

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.

Reflectance Analysis of Sputtered Indium Tin Oxide(ITO) Using UV Lambda

Preliminary analysis has been done on the reflectance of sputtered Indium Tin Oxide (ITO) layers. The analysis is done for two different types of layers which is the directly sputtered ITO films and the treated ITO films. In both type of the film it is divided into the thickness of the layer and deposition time. Analysis is done using Perkin Elmer Lambda 950 UV/Vis/NIR Spectrophotometer. The working spectral range is from 250 nm to 800 nm (for transmittance), covering the ultra-violet (UV) and visible spectrum. Results shows thatthe directly deposited thin ITO films had lower reflectance compared to the thick films. The reflectance of the thick films with three and four layers was high (95%) compared to the rest of the films. The treated films produce very low reflectance.

Preliminary Study on Resistance of Non-Treated and Treated ITO Films

A study on the resistance of directly sputtered films and treated films of Indium Tin Oxide (ITO) is done to initiate an extensive study on the material. This study involves variation in terms of number of layers and duration of deposition. Treated films are produced by undergoing annealing process which is carried out using Split Type Tube Furnace. Resistance measurements were carried out using Semiconductor Parametric Analyzer (SPA). Results show that the directly sputtered ITO films produced lower resistance compared to the treated ITO films.

Wettability Study Using O2 and Ar RIE Gas Treatment on Aluminium Surface

Wettability is one of the most important aspects in microfluid technology. The effect of surface roughness on the wettability by a liquid has been studied experimentally using Design of Experiment(DOE). Sixteen samples were etched using Reactive Ion Etching (RIE) technique with different combination of parameters. RIE parameters concerned in this experiment are ratio of Oxygen, Argon, ICP power and BIAS power. Reactive Ion Etching influences surface morphology which is correlated with the contact angle produced. This preliminary study is to gain information on the how does RIE affects the aluminum bondpad in terms of surface roughness and contact angle.

Surface Roughness Influence on O2 and Ar RIE Gas Treated Aluminum Surface

This study reports on the preliminary investigations on the effect of Reactive Ion Etch (RIE) parameters on the surface characteristics of Al bond pad. Investigation is done employing Design of Experiment (DOE) method. Quantity of Oxygen, Argon, ICP power and BIAS power were varied to get 16 sets of recipes. This provides 16 samples with different combination of RIE parameters. Surface characteristics of the samples were analyzed using Atomic Force Microscopy (AFM).Data collected were in terms of Surface Roughness (RA), Peak Vs Valley (P-V) and Surface Root-Mean-Square Roughness (RMS). Result shows that combination of these RIE parameters does not vastly affect the surface characteristics of the Al bond pad.

Effect of High Temperature during Electroless Nickel Process

This paper presents the correlation between electroless process time, immersion gold process time and the bump height in electroless nickel immersion gold (ENIG). A certain bump height need to be achieved in order to create acceptable solder bumps for reflow process. The study was done using a full factorial design of experiment (DOE). The DOE matrix is made of two levels with two factors. Analysis was done by plotting the main effects plot for each factor. The results suggest that higher process time increases the plating rate where the temperature fixed at 100 °C. It can be concluded that electroless nickel time has more influence to the bump height compared to immersion gold time.

Reactive Ion Etching Parameter Effect on Aluminum Bond Pad Surface Morphology

Reactive Ion Etching (RIE) is an important process in fabrication of semiconductor devices. Design Of Experiment (DOE) has been used to study the effect of Reactive Ion Etch (RIE) towards surface morphology of aluminum bond pad. Important RIE factors involved in this experimental study are ratio of Tetrafluoromethane (CF4), Argon gas flow, BIAS, and ICP power. Different combinations of these factors produces different results of surface morphologies which was obtained using Atomic Force Microscopic (AFM). Produced results shows that overall surface roughness of the pad is affected by RIE and DOE offers a better way to optimize the desired outcome.

Wettability and Surface Roughness Study on RIE Treated Aluminium Deposited Surface

Design of Experiment (DOE) is a technique for optimizing process which has controllable inputs and measurable outputs. As a method of DOE, 24 Full Factorial design is used to study the effect of Reactive Ion Etch towards the surface roughness of aluminum pad and effect of the roughness produced towards the contact angle. Surface roughness analysis is done using Atomic Force Microscop (AFM). Contact angle is measured using AutoCad software from the images captured from droplet test. This contact angles must be more than 90° for non-wetting profile or less than 90° for wetting profile. This work is also done to understand the interaction between the process parameters and how each parameters will affect the etch rate. The results are analyzed which shows that the increase in surface roughness produces an increase on the contact angle and vice versa.

Different Shear Height Stress Evaluation on -0.7Cu Based Lead Free Solder

Interconnection technology has improved by leaps and bounds since the advent of solder reflow. This has made surface mount technology more robust. Ball Grid Array (BGA) is a demanding surface mount chip package in Integrated Circuits (IC) which uses a grid of solder balls as its connectors. In this preliminary study, load effects of shear test on a single solder joint with varied parameters are briefly discussed. A suitable lead-free solder is used in this study which is Sn-3.5Ag-0.7Cu. Simple Single Factor (SSF) method was used to execute this experimental study. Ansys software was used to simulate and investigate the stress response on a single solder ball joints. The results shows that when the shear height is high the shear stress is reduced.

Aluminium Surface Grain Size Analysis on RIE Treatment

Reactive Ion Etch (RIE) has been an important process in the world of microelectronic fabrication. Focus of this preliminary study is on how RIE affects the grain size of aluminum film which is fabricated on substrates. RIE parameters are varied to obtain 16 different recipes which are done using Design of Experiment. Grain size of the samples is recorded for all 16 samples before and after RIE treatment. This produces results that can be compared to obtain the effect of RIE on the aluminum film. Results show that RIE affects the mean grain size of the aluminum film as it increases after RIE treatment.