Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect

Structural integrity of wire bonding interconnection is having a significant impact on the quality of microelectronic devices. Conventional electrical test methodology is unable to detect 1 to 20 m of cracks that exists in wire bond stitch weld. This micro crack has becomes prominent in Power MO...

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Main Author: Robin, Ong Su Kiat
Format: Thesis
Language:English
Published: 2016
Subjects:
Online Access:http://eprints.usm.my/45796/
http://eprints.usm.my/45796/1/Time%20Domain%20Reflection%20Method%20To%20Detect%20Copper%20Wire%20Micro%20Crack%20Weld%20Defect.pdf
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author Robin, Ong Su Kiat
author_facet Robin, Ong Su Kiat
author_sort Robin, Ong Su Kiat
building USM Institutional Repository
collection Online Access
description Structural integrity of wire bonding interconnection is having a significant impact on the quality of microelectronic devices. Conventional electrical test methodology is unable to detect 1 to 20 m of cracks that exists in wire bond stitch weld. This micro crack has becomes prominent in Power MOSFET Molded Leadless Package (MLP) with copper wire of 38 m in diameter and 800 m long. In this research, total 1368 units of Power MOSFETs was tested using a Credence ASL1000 tester. The aim of this research is to investigate an alternative methodology by establishing a comprehensive physical and simulation characterization technique namely Time Domain Reflectometry (TDR) to address this issue. Parameters that have been investigated included TDR input (frequency of 20 and 50 GHz and time domain between 10 to 23 psec) and output (reflection voltage from 0 to 250 mV and characteristic impedance) responses on the wire crack geometries (length from 1 to 20 m and crack area). 50 GHz TDR successfully detected 10, 50 and 90 % of crack size with physical length of 1, 4 and 10 m respectively. In order to complement with the TDR results, other non-destructive 2D & 3D X-ray Computed Tomography (CT) and destructive Scanning Electron Microscopy (SEM) characterization techniques have been used. Simulation of crack weld length and crack area has also been performed, in order to estimate the physical crack dimension without using the actual TDR instrument. Besides, a prediction of TDR response on both reflection voltage and impedance change have also been verified. Novelty of this work is on the non-destructive electrical test methodology that able to detect micro crack defect at wedge bond in a Power MOSFET gate wire. This effective technique offers up to physical dimension of 1 m and simulated dimension of 10 m comparing with other techniques. TDR has overcome the conventional test limitation and achieved a novel approach through the defined detection resolution for micro crack weld.
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spelling usm-457962021-11-17T03:42:17Z http://eprints.usm.my/45796/ Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect Robin, Ong Su Kiat T Technology TA401-492 Materials of engineering and construction. Mechanics of materials Structural integrity of wire bonding interconnection is having a significant impact on the quality of microelectronic devices. Conventional electrical test methodology is unable to detect 1 to 20 m of cracks that exists in wire bond stitch weld. This micro crack has becomes prominent in Power MOSFET Molded Leadless Package (MLP) with copper wire of 38 m in diameter and 800 m long. In this research, total 1368 units of Power MOSFETs was tested using a Credence ASL1000 tester. The aim of this research is to investigate an alternative methodology by establishing a comprehensive physical and simulation characterization technique namely Time Domain Reflectometry (TDR) to address this issue. Parameters that have been investigated included TDR input (frequency of 20 and 50 GHz and time domain between 10 to 23 psec) and output (reflection voltage from 0 to 250 mV and characteristic impedance) responses on the wire crack geometries (length from 1 to 20 m and crack area). 50 GHz TDR successfully detected 10, 50 and 90 % of crack size with physical length of 1, 4 and 10 m respectively. In order to complement with the TDR results, other non-destructive 2D & 3D X-ray Computed Tomography (CT) and destructive Scanning Electron Microscopy (SEM) characterization techniques have been used. Simulation of crack weld length and crack area has also been performed, in order to estimate the physical crack dimension without using the actual TDR instrument. Besides, a prediction of TDR response on both reflection voltage and impedance change have also been verified. Novelty of this work is on the non-destructive electrical test methodology that able to detect micro crack defect at wedge bond in a Power MOSFET gate wire. This effective technique offers up to physical dimension of 1 m and simulated dimension of 10 m comparing with other techniques. TDR has overcome the conventional test limitation and achieved a novel approach through the defined detection resolution for micro crack weld. 2016-12 Thesis NonPeerReviewed application/pdf en http://eprints.usm.my/45796/1/Time%20Domain%20Reflection%20Method%20To%20Detect%20Copper%20Wire%20Micro%20Crack%20Weld%20Defect.pdf Robin, Ong Su Kiat (2016) Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect. PhD thesis, Universiti Sains Malaysia.
spellingShingle T Technology
TA401-492 Materials of engineering and construction. Mechanics of materials
Robin, Ong Su Kiat
Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title_full Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title_fullStr Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title_full_unstemmed Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title_short Time Domain Reflection Method To Detect Copper Wire Micro Crack Weld Defect
title_sort time domain reflection method to detect copper wire micro crack weld defect
topic T Technology
TA401-492 Materials of engineering and construction. Mechanics of materials
url http://eprints.usm.my/45796/
http://eprints.usm.my/45796/1/Time%20Domain%20Reflection%20Method%20To%20Detect%20Copper%20Wire%20Micro%20Crack%20Weld%20Defect.pdf