Michael Bozack - Academia.edu (original) (raw)
Papers by Michael Bozack
56th Electronic Components and Technology Conference 2006, 2006
Solder materials demonstrate evolving microstructure and mechanical behavior that changes signifi... more Solder materials demonstrate evolving microstructure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders have been performed. Extreme care has been taken so that the fabricated solder uniaxial test specimens accurately reflect the solder materials present in actual lead free solder joints. A novel specimen preparation procedure has been developed where the solder uniaxial test specimens are formed in high precision rectangular cross-section glass tubes using a vacuum suction process. The tubes are then sent through a SMT reflow to re-melt the solder in the tubes and subject them to any desired temperature profile (i.e. same as actual solder joints).
2007 Proceedings 57th Electronic Components and Technology Conference, 2007
The microstructure, mechanical response, and failure behavior of lead free solder joints in elect... more The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. In our prior work on aging effects (Ma, et al., ECTC 2006), we demonstrated that the observed material behavior variations of SAC405 and SAC305 lead free solders during room temperature aging (25 1-4244-0985-3/07/$25.00 ©2007 IEEE
IEEE Transactions on Components, Packaging and Manufacturing Technology, 2012
Relatively little is known about the fretting mechanism of high power connectors used in hybrid v... more Relatively little is known about the fretting mechanism of high power connectors used in hybrid vehicles, even though the vehicles are widely being introduced to the market. This paper experimentally investigates the fretting mechanisms of silver-plated high power connectors caused by vibrations. In order to emulate operational and environmental effects, a test stand was designed that is capable of measuring electrical contact resistance (ECR), relative displacement and connector temperature. The experimental results show that the variation of ECR of connectors subject to vibration is primarily due to periodic changes of contact area caused by relative motion between the contact interfaces, rather than other fretting corrosions. This finding was reinforced by observing a good correlation between relative motion and the increase of ECR under vibration. When a vibration stops, the ECR decreased to a value that is slightly larger than the original value. A surface analysis shows no obvious corrosion until the coating is worn away. In addition, the effect of high current on the fretting mechanism is also investigated.
2011 IEEE 57th Holm Conference on Electrical Contacts (Holm), 2011
Abstract This paper explores the notion that the nucleation and growth of Sn whiskers is motivate... more Abstract This paper explores the notion that the nucleation and growth of Sn whiskers is motivated by net compressive intrinsic thin film stresses. In this view, a threshold level of stress should exist at which Sn whiskers nucleate; furthermore, whiskering will relieve the compressive stress by a measurable amount. We examine the threshold stress for whisker nucleation and measure the amount of stress relieved during Sn whisker growth on brass substrates. The stress evolution has been evaluated by traditional bent beam analysis via ...
Materials Science Forum, 2006
... NCC8-237. References [1] ED Luckowski, JM Delucca, JR Williams, SE Mohney, MJ Bozack, T. Isaa... more ... NCC8-237. References [1] ED Luckowski, JM Delucca, JR Williams, SE Mohney, MJ Bozack, T. Isaac-Smith and J. Crofton: J. Electronic Materials 27(4) (1998), p. 330. ... [7] AV Adedeji, AC Ahyi, JR Williams, M. Horsey, SE Mohney and JD Scofield: Proc. ...
The Ninth Intersociety Conference on Thermal and Thermomechanical Phenomena In Electronic Systems (IEEE Cat. No.04CH37543), 2004
The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been ... more The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been a long time concern for systems exposed to harsh environments such as those found in automotive and aerospace applications. This is due to a combination of the extreme temperature ...
2010 Proceedings of the 56th IEEE Holm Conference on Electrical Contacts, 2010
Relatively little is known about the fretting mechanism of high power connectors used in hybrid v... more Relatively little is known about the fretting mechanism of high power connectors used in hybrid vehicles, even though the vehicles are widely being introduced to the market. This work experimentally investigates the fretting mechanisms of silver-plated high power connectors caused by vibrations. In order to emulate operational and environmental effects, a test stand was designed that is capable of measuring ECR, relative displacement and connector temperature. The experimental results show that the variation of electrical contact resistance (ECR) of connectors subject to vibration is primarily due to periodic changes of contact area caused by relative motion between the contact interfaces, rather than other fretting corrosions. This finding is reinforced by observing a good correlation between relative motion and the increase of ECR under vibration. When a vibration stopped, the ECR decreased to a value that is slightly larger than the original value. A surface analysis showed no obvious corrosion until the coating was worn away.
EuroSimE 2008 - International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Micro-Systems, 2008
Solder materials demonstrate evolving microstructure and mechanical behavior that changes signifi... more Solder materials demonstrate evolving microstructure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These physical aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders
2010 Proceedings 60th Electronic Components and Technology Conference (ECTC), 2010
The microstructure, mechanical response, and failure behavior of lead free solder joints in elect... more The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. In our prior work on aging effects, we have demonstrated that large degradations occur in the material properties (stiffness and strength) and creep behavior of Sn-Ag-Cu (SAC) lead free solders during aging. These
IEEE Holm Conference on Electrical Contacts, 2004
The objective of this work is to develop a greater understanding of the mechanisms controlling fr... more The objective of this work is to develop a greater understanding of the mechanisms controlling fretting under various vibration conditions. This information is intended to provide a basis for understanding and reducing this potential problem in automotive connectors. Toward this end, an experimental study of connector samples under multi-frequency vibration has been conducted. The primary connector being investigated is a
Physical Chemistry of Interfaces and Nanomaterials III, 2004
The electronic structure of SWNTs was investigated using the complementary techniques of single m... more The electronic structure of SWNTs was investigated using the complementary techniques of single molecule photoluminescence spectroscopy and ultrafast optical spectroscopy. We found that photoexcited electrons in SWNTs isolated in surfactant micelles decay through many channels exhibiting a range of decay times (~200 fs to ~ 120 ps). The magnitude of the longest-lived component in the ultrafast signal specifically depends on
One of the important applications for which wireless phage-immobilized magnetoelastic (ME) biosen... more One of the important applications for which wireless phage-immobilized magnetoelastic (ME) biosensors are being developed is the real-time detection of pathogenic bacteria for bio-security and food safety. Until now, such ME biosensors have been manufactured by ...
2001 Proceedings. 51st Electronic Components and Technology Conference (Cat. No.01CH37220), 2001
For a successful transition to Pb-free manufacturing in electronics assembly, it is critical to u... more For a successful transition to Pb-free manufacturing in electronics assembly, it is critical to understand the behavior of Pb-free solders (in bulk and paste form) and their interaction with the Pb-free Printed Wiring Board (PWB) finishes. This paper presents the results obtained from the spread tests of several Pb-free solder pastes when reflowed on Pb-free PWB finishes. The solder alloys
Nanoengineering: Fabrication, Properties, Optics, and Devices, 2004
Micro- and nano-MEMS technology is being increasingly exploited in biomedical applications, such ... more Micro- and nano-MEMS technology is being increasingly exploited in biomedical applications, such as large electrode-count neural prosthesis probe arrays. However, a bottleneck in fully utilizing this technology has been the interconnect between the implanted MEMS device and the external system connected to the implanted device. Since the implanted MEMS device is capable of having a large number of elements, the
2008 Proceedings of the 54th IEEE Holm Conference on Electrical Contacts, 2008
... One of the earliest studies on fretting degradation was presented in 1974 by Whitley and Bock... more ... One of the earliest studies on fretting degradation was presented in 1974 by Whitley and Bock [1]. Detailed surveys of work in the area are provided by Antler [2] (up to 1984) and by Malucci [4] for more recent ... Bretton I. Rickett, Robert D. Malucci, and Charlie Manlapaz Molex, Inc ...
Solid-State Electronics, 2008
Thermal oxides on the Ga-face of low defect density bulk gallium nitride (GaN) were controllably ... more Thermal oxides on the Ga-face of low defect density bulk gallium nitride (GaN) were controllably produced under varying conditions and subsequently analyzed. The thermal oxidation was performed in a dry oxygen atmosphere at different temperatures and different oxidation times. Each ...
Soldering & Surface Mount Technology, 2004
Introduction Legislation that mandates the banning of lead in electronics, due to environmental a... more Introduction Legislation that mandates the banning of lead in electronics, due to environmental and health concerns, has been actively pursued in several countries during the past 15 years. Although the products covered by and implementation deadlines for such ...
physica status solidi (c), 2011
Langmuir, 2003
Self-assembled monolayers of thioctic acid (1,2-dithiolane-3-pentanoic acid) on Au surfaces were ... more Self-assembled monolayers of thioctic acid (1,2-dithiolane-3-pentanoic acid) on Au surfaces were studied by electrochemical desorption experiments and X-ray photoelectron spectroscopy. The cathodic stripping of thioctic acid monolayers from Au electrodes in 0.5 ...
Journal of the American Chemical Society, 2004
Cross-linking of sulfonated poly(ether-ether)ketone-poly(vinyl alcohol) (SPEEK-PVA) materials yie... more Cross-linking of sulfonated poly(ether-ether)ketone-poly(vinyl alcohol) (SPEEK-PVA) materials yields flexible polymer films, possessing high light-sensitivity and ion-exchange capabilities. Adsorbed Ag+ ions are photoreduced in the film under illumination (lambda = 350 nm), leading to metal nanoparticle formation in places where the film has been exposed to the light. Nanoparticles form via reduction of Ag+ by the polymeric alcohol radicals, generated in the system as a result of photochemical H-abstraction from PVA molecules by the excited carbonyl triplet state of SPEEK. Use of the films for direct metal photopatterning is demonstrated.
56th Electronic Components and Technology Conference 2006, 2006
Solder materials demonstrate evolving microstructure and mechanical behavior that changes signifi... more Solder materials demonstrate evolving microstructure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders have been performed. Extreme care has been taken so that the fabricated solder uniaxial test specimens accurately reflect the solder materials present in actual lead free solder joints. A novel specimen preparation procedure has been developed where the solder uniaxial test specimens are formed in high precision rectangular cross-section glass tubes using a vacuum suction process. The tubes are then sent through a SMT reflow to re-melt the solder in the tubes and subject them to any desired temperature profile (i.e. same as actual solder joints).
2007 Proceedings 57th Electronic Components and Technology Conference, 2007
The microstructure, mechanical response, and failure behavior of lead free solder joints in elect... more The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. In our prior work on aging effects (Ma, et al., ECTC 2006), we demonstrated that the observed material behavior variations of SAC405 and SAC305 lead free solders during room temperature aging (25 1-4244-0985-3/07/$25.00 ©2007 IEEE
IEEE Transactions on Components, Packaging and Manufacturing Technology, 2012
Relatively little is known about the fretting mechanism of high power connectors used in hybrid v... more Relatively little is known about the fretting mechanism of high power connectors used in hybrid vehicles, even though the vehicles are widely being introduced to the market. This paper experimentally investigates the fretting mechanisms of silver-plated high power connectors caused by vibrations. In order to emulate operational and environmental effects, a test stand was designed that is capable of measuring electrical contact resistance (ECR), relative displacement and connector temperature. The experimental results show that the variation of ECR of connectors subject to vibration is primarily due to periodic changes of contact area caused by relative motion between the contact interfaces, rather than other fretting corrosions. This finding was reinforced by observing a good correlation between relative motion and the increase of ECR under vibration. When a vibration stops, the ECR decreased to a value that is slightly larger than the original value. A surface analysis shows no obvious corrosion until the coating is worn away. In addition, the effect of high current on the fretting mechanism is also investigated.
2011 IEEE 57th Holm Conference on Electrical Contacts (Holm), 2011
Abstract This paper explores the notion that the nucleation and growth of Sn whiskers is motivate... more Abstract This paper explores the notion that the nucleation and growth of Sn whiskers is motivated by net compressive intrinsic thin film stresses. In this view, a threshold level of stress should exist at which Sn whiskers nucleate; furthermore, whiskering will relieve the compressive stress by a measurable amount. We examine the threshold stress for whisker nucleation and measure the amount of stress relieved during Sn whisker growth on brass substrates. The stress evolution has been evaluated by traditional bent beam analysis via ...
Materials Science Forum, 2006
... NCC8-237. References [1] ED Luckowski, JM Delucca, JR Williams, SE Mohney, MJ Bozack, T. Isaa... more ... NCC8-237. References [1] ED Luckowski, JM Delucca, JR Williams, SE Mohney, MJ Bozack, T. Isaac-Smith and J. Crofton: J. Electronic Materials 27(4) (1998), p. 330. ... [7] AV Adedeji, AC Ahyi, JR Williams, M. Horsey, SE Mohney and JD Scofield: Proc. ...
The Ninth Intersociety Conference on Thermal and Thermomechanical Phenomena In Electronic Systems (IEEE Cat. No.04CH37543), 2004
The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been ... more The solder joint reliability of ceramic chip resistors assembled to laminate substrates has been a long time concern for systems exposed to harsh environments such as those found in automotive and aerospace applications. This is due to a combination of the extreme temperature ...
2010 Proceedings of the 56th IEEE Holm Conference on Electrical Contacts, 2010
Relatively little is known about the fretting mechanism of high power connectors used in hybrid v... more Relatively little is known about the fretting mechanism of high power connectors used in hybrid vehicles, even though the vehicles are widely being introduced to the market. This work experimentally investigates the fretting mechanisms of silver-plated high power connectors caused by vibrations. In order to emulate operational and environmental effects, a test stand was designed that is capable of measuring ECR, relative displacement and connector temperature. The experimental results show that the variation of electrical contact resistance (ECR) of connectors subject to vibration is primarily due to periodic changes of contact area caused by relative motion between the contact interfaces, rather than other fretting corrosions. This finding is reinforced by observing a good correlation between relative motion and the increase of ECR under vibration. When a vibration stopped, the ECR decreased to a value that is slightly larger than the original value. A surface analysis showed no obvious corrosion until the coating was worn away.
EuroSimE 2008 - International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Micro-Systems, 2008
Solder materials demonstrate evolving microstructure and mechanical behavior that changes signifi... more Solder materials demonstrate evolving microstructure and mechanical behavior that changes significantly with environmental exposures such as isothermal aging and thermal cycling. These physical aging effects are greatly exacerbated at higher temperatures typical of thermal cycling qualification tests for harsh environment electronic packaging. In the current study, mechanical measurements of thermal aging effects and material behavior evolution of lead free solders
2010 Proceedings 60th Electronic Components and Technology Conference (ECTC), 2010
The microstructure, mechanical response, and failure behavior of lead free solder joints in elect... more The microstructure, mechanical response, and failure behavior of lead free solder joints in electronic assemblies are constantly evolving when exposed to isothermal aging and/or thermal cycling environments. In our prior work on aging effects, we have demonstrated that large degradations occur in the material properties (stiffness and strength) and creep behavior of Sn-Ag-Cu (SAC) lead free solders during aging. These
IEEE Holm Conference on Electrical Contacts, 2004
The objective of this work is to develop a greater understanding of the mechanisms controlling fr... more The objective of this work is to develop a greater understanding of the mechanisms controlling fretting under various vibration conditions. This information is intended to provide a basis for understanding and reducing this potential problem in automotive connectors. Toward this end, an experimental study of connector samples under multi-frequency vibration has been conducted. The primary connector being investigated is a
Physical Chemistry of Interfaces and Nanomaterials III, 2004
The electronic structure of SWNTs was investigated using the complementary techniques of single m... more The electronic structure of SWNTs was investigated using the complementary techniques of single molecule photoluminescence spectroscopy and ultrafast optical spectroscopy. We found that photoexcited electrons in SWNTs isolated in surfactant micelles decay through many channels exhibiting a range of decay times (~200 fs to ~ 120 ps). The magnitude of the longest-lived component in the ultrafast signal specifically depends on
One of the important applications for which wireless phage-immobilized magnetoelastic (ME) biosen... more One of the important applications for which wireless phage-immobilized magnetoelastic (ME) biosensors are being developed is the real-time detection of pathogenic bacteria for bio-security and food safety. Until now, such ME biosensors have been manufactured by ...
2001 Proceedings. 51st Electronic Components and Technology Conference (Cat. No.01CH37220), 2001
For a successful transition to Pb-free manufacturing in electronics assembly, it is critical to u... more For a successful transition to Pb-free manufacturing in electronics assembly, it is critical to understand the behavior of Pb-free solders (in bulk and paste form) and their interaction with the Pb-free Printed Wiring Board (PWB) finishes. This paper presents the results obtained from the spread tests of several Pb-free solder pastes when reflowed on Pb-free PWB finishes. The solder alloys
Nanoengineering: Fabrication, Properties, Optics, and Devices, 2004
Micro- and nano-MEMS technology is being increasingly exploited in biomedical applications, such ... more Micro- and nano-MEMS technology is being increasingly exploited in biomedical applications, such as large electrode-count neural prosthesis probe arrays. However, a bottleneck in fully utilizing this technology has been the interconnect between the implanted MEMS device and the external system connected to the implanted device. Since the implanted MEMS device is capable of having a large number of elements, the
2008 Proceedings of the 54th IEEE Holm Conference on Electrical Contacts, 2008
... One of the earliest studies on fretting degradation was presented in 1974 by Whitley and Bock... more ... One of the earliest studies on fretting degradation was presented in 1974 by Whitley and Bock [1]. Detailed surveys of work in the area are provided by Antler [2] (up to 1984) and by Malucci [4] for more recent ... Bretton I. Rickett, Robert D. Malucci, and Charlie Manlapaz Molex, Inc ...
Solid-State Electronics, 2008
Thermal oxides on the Ga-face of low defect density bulk gallium nitride (GaN) were controllably ... more Thermal oxides on the Ga-face of low defect density bulk gallium nitride (GaN) were controllably produced under varying conditions and subsequently analyzed. The thermal oxidation was performed in a dry oxygen atmosphere at different temperatures and different oxidation times. Each ...
Soldering & Surface Mount Technology, 2004
Introduction Legislation that mandates the banning of lead in electronics, due to environmental a... more Introduction Legislation that mandates the banning of lead in electronics, due to environmental and health concerns, has been actively pursued in several countries during the past 15 years. Although the products covered by and implementation deadlines for such ...
physica status solidi (c), 2011
Langmuir, 2003
Self-assembled monolayers of thioctic acid (1,2-dithiolane-3-pentanoic acid) on Au surfaces were ... more Self-assembled monolayers of thioctic acid (1,2-dithiolane-3-pentanoic acid) on Au surfaces were studied by electrochemical desorption experiments and X-ray photoelectron spectroscopy. The cathodic stripping of thioctic acid monolayers from Au electrodes in 0.5 ...
Journal of the American Chemical Society, 2004
Cross-linking of sulfonated poly(ether-ether)ketone-poly(vinyl alcohol) (SPEEK-PVA) materials yie... more Cross-linking of sulfonated poly(ether-ether)ketone-poly(vinyl alcohol) (SPEEK-PVA) materials yields flexible polymer films, possessing high light-sensitivity and ion-exchange capabilities. Adsorbed Ag+ ions are photoreduced in the film under illumination (lambda = 350 nm), leading to metal nanoparticle formation in places where the film has been exposed to the light. Nanoparticles form via reduction of Ag+ by the polymeric alcohol radicals, generated in the system as a result of photochemical H-abstraction from PVA molecules by the excited carbonyl triplet state of SPEEK. Use of the films for direct metal photopatterning is demonstrated.