A model of lightly doped drain n-MOSFET degradation in drain current under long-term AC use condi... more A model of lightly doped drain n-MOSFET degradation in drain current under long-term AC use conditions which includes a self-limiting effect in the hot-electron induced device degradation is proposed for lifetime projections. Experimental results on LDD n-MOSFETs (W=50 μm) are presented which show the maximum drain current degradation as a function of the average substrate current under the various AC
approved: Redacted for Privacy Thomas K. Plant The purpose of this work is to develop an accurate... more approved: Redacted for Privacy Thomas K. Plant The purpose of this work is to develop an accurate non-contacting displacement sensor for use in industrial environments. The accurate measurement of small displacements is important for many industrial process applications such as lumber sawing, paper production and robot position sensing. A simple technique for the measurement of small displacements has been developed using semiconductor diode lasers in a heterodyne laser ranging system. Two collimated diode lasers are directly amplitude modulated at fm and fm + fb where fm is 10 300 MHz and fb is 10 50 KHz. One laser beam is reflected off the target and focused onto a detector along with the other (local oscillator) laser beam. A heterodyne signal at the beat frequency (fb) is produced. Small displacements cause a phase shift between the local oscillator signal and the collected signal from the target. Displacement sensing accuracies of 1.4 um and 50 nm have been calculated and measu...
1999 Proceedings. 49th Electronic Components and Technology Conference (Cat. No.99CH36299)
The failure and yield on the preliminary result of our pioneer fabrication line of 155 Mbps OTMs ... more The failure and yield on the preliminary result of our pioneer fabrication line of 155 Mbps OTMs adopting a modern Si V-groove and FCB techniques have been studied. The yields of LD purge, sub-module assembly, and final assembly were found to be 78%, 95%, and 77% respectively out of total 319 samples. The yield of whole fabrication process has been found to be 57%, where it can be improved to be 70% or higher by replacing the electrical component assembly process with more advanced IC process.
The purpose of this work is to develop an accurate non-contacting displacement sensor for use in ... more The purpose of this work is to develop an accurate non-contacting displacement sensor for use in industrial environments. The accurate measurement of small displacements is important for many industrial process applications such as lumber sawing, paper production and robot position sensing. A simple technique for the measurement of small displacements has been developed using semiconductor diode lasers in a heterodyne laser ranging system. Two collimated diode lasers are directly amplitude modulated at fm and fm + fb where fm is 10- 300 MHz and fb is 10- 50 KHz. One laser beam is reflected off the target and focused onto a detector along with the other (local oscillator) laser beam. A heterodyne signal at the beat frequency (fb) is produced. Small displacements cause a phase shift between the local oscillator signal and the collected signal from the target. Displacement sensing accuracies of 1.4 um and 50 nm have been calculated and measured over dynamic ranges of 3.5 m and 1 cm for fm = 10 MHz and 300 MHz, respectively. It has been shown that using heterodyne laser ranging with diode lasers is an accurate displacement measurement technique for industrial applications.
MOSFET degradation due to hot carrier injection is the most important reliability issue in realiz... more MOSFET degradation due to hot carrier injection is the most important reliability issue in realizing submicron ultralarge scaled integrated circuits. This degradation has been widely studied and lifetime simulators have also been developed for digital circuit operation [1]-[2]. On the other hand, the degradation of analog device parameters such as drain conductance due to hot carrier injection are not clearly understood and modeled. In this paper, we propose, for the first time, a physical model of analog drain conductance, gd degradation based on mobility reduction due to hot carrier generated interface states and show a reliability design guideline for analog devices.
Proceedings of the 5th Electronics Packaging Technology Conference (EPTC 2003)
Failure mechanisms in plastic packaged optocouplers have been investigated. The high failure rate... more Failure mechanisms in plastic packaged optocouplers have been investigated. The high failure rate of the optocouplers, specifically the reverse bias leakage current of the light emitting diodes (LEDs), was found to be moisturerelated. Using scanning electron microscopy coupled with energy dispersive X-ray microanalysis, a significant concentration of copper was detected on the surface of failed LEDs, possibly migrated from the copper leadframe. By applying infra-red photoemmision microscopy it was found that bandgap emission was associated with the reverse leakage path in the area of the pn junction of the LEDs.
2008 15th International Symposium on the Physical and Failure Analysis of Integrated Circuits, 2008
Failure mechanisms of light emitting diodes (LEDs) have been investigated. Various failure patter... more Failure mechanisms of light emitting diodes (LEDs) have been investigated. Various failure patterns of LEDs for general lighting applications were simulated under high electrical and thermal stress test conditions. Using scanning electron microscopy related with I-V characterization before and after the stress simulation, a representative failure pattern of LEDs matrixed in terms of the electrical parameter shifts and physical conditions observed after decapsulation. By applying photo-emission microscopy it was found that local damage of LED surface was caused by excessive high temperature in the area of the pn junction of LEDs.
Lasers and Electro-Optics Society, IEEE LEOS Annual Meeting, 1995
In this paper, low PWS (post-weld shift) and large aligning tolerance DFB-LD (distributed feedbac... more In this paper, low PWS (post-weld shift) and large aligning tolerance DFB-LD (distributed feedback laser diode) modules and APD (avalanche photodiode) modules were obtained by combining proper package design and the development of a laser welding technique. The welded parts of the modules were analyzed in terms of laser welding parameters, cross-section analysis and shear strength tests
ABSTRACT A novel reliability projection model of semiconductor laser diodes (LD) is presented. By... more ABSTRACT A novel reliability projection model of semiconductor laser diodes (LD) is presented. By correlating initial thermal characteristics and long-term degradation, a relationship between LD degradation and ambient temperature has been investigated. The proposed model is found to be efficient for the reliability projection of LDs, which requires a thermal characterization only at t=0
Technical Digest. CLEO/Pacific Rim '99. Pacific Rim Conference on Lasers and Electro-Optics (Cat. No.99TH8464)
Conventionally, optical communication modules for subscriber have been composed of transmitter an... more Conventionally, optical communication modules for subscriber have been composed of transmitter and receiver as separated or combined requiring two lines of optical fibers to constitute a network. To realize the fiber-to-the-home (FTTH), it is necessary to make the cheaper and more compact module as well as to reduce the fiber installation cost. In this study, an accurate silicon optical bench (SiOB) has been designed for passive integration of bidirectional transceiver sub-module. Optical coupling between the transceiver chip and a single mode fiber is accomplished by aligning an acute angle-faceted fiber on the V-groove of SiOB to the front facet of the flip-chip bonded chip. Transmitted light from the laser diode of the transceiver chip is coupled into fiber core as in usual buff coupling, while receiving light from the fiber is refracted downward by Snell's law and absorbed into pin-PD's photosensitive area after being reflected at the metal coated V-groove side-wall
Using a specifically designed test structure applying human body model electrostatic discharge (E... more Using a specifically designed test structure applying human body model electrostatic discharge (ESD) stress, the origin of dielectric breakdown in Cu/low-κ interconnect systems was found to be in interfacial delamination. The interfacial delamination between a SiC capping layer and a SiOC interdielectric layer is responsible for the increase of intermetal dielectric leakage current, causing high current Joule heating as well
In this letter, we report the high performance GaNbased light-emitting diodes (LEDs) with embedde... more In this letter, we report the high performance GaNbased light-emitting diodes (LEDs) with embedded air void array grown by metal-organic chemical vapor deposition. The donut-shaped air void was formed at the interface between crown-shaped patterned sapphire substrates (CPSS) and the GaN epilayer by conventional photolithography. The transmission electron microscopy images demonstrate that the threading dislocations were significantly suppressed by epitaxial lateral overgrowth (ELOG). The Monte Carlo ray-tracing simulation reveals that the light extraction of the air-voids embedded LED was dramatically increased due to a strong light reflection and redirection by the air voids.
Proceedings 1993 International Workshop on Vlsi Process and Device Modeling, May 14, 1993
MOSFET degradation due to hot carrier injection is the most important reliability issue in realiz... more MOSFET degradation due to hot carrier injection is the most important reliability issue in realizing submicron ultralarge scaled integrated circuits. This degradation has been widely studied and lifetime simulators have also been developed for digital circuit operation [1]-[2]. On the other hand, the degradation of analog device parameters such as drain conductance due to hot carrier injection are not clearly understood and modeled. In this paper, we propose, for the first time, a physical model of analog drain conductance, gd degradation based on mobility reduction due to hot carrier generated interface states and show a reliability design guideline for analog devices.
A model of lightly doped drain n-MOSFET degradation in drain current under long-term AC use condi... more A model of lightly doped drain n-MOSFET degradation in drain current under long-term AC use conditions which includes a self-limiting effect in the hot-electron induced device degradation is proposed for lifetime projections. Experimental results on LDD n-MOSFETs (W=50 μm) are presented which show the maximum drain current degradation as a function of the average substrate current under the various AC
approved: Redacted for Privacy Thomas K. Plant The purpose of this work is to develop an accurate... more approved: Redacted for Privacy Thomas K. Plant The purpose of this work is to develop an accurate non-contacting displacement sensor for use in industrial environments. The accurate measurement of small displacements is important for many industrial process applications such as lumber sawing, paper production and robot position sensing. A simple technique for the measurement of small displacements has been developed using semiconductor diode lasers in a heterodyne laser ranging system. Two collimated diode lasers are directly amplitude modulated at fm and fm + fb where fm is 10 300 MHz and fb is 10 50 KHz. One laser beam is reflected off the target and focused onto a detector along with the other (local oscillator) laser beam. A heterodyne signal at the beat frequency (fb) is produced. Small displacements cause a phase shift between the local oscillator signal and the collected signal from the target. Displacement sensing accuracies of 1.4 um and 50 nm have been calculated and measu...
1999 Proceedings. 49th Electronic Components and Technology Conference (Cat. No.99CH36299)
The failure and yield on the preliminary result of our pioneer fabrication line of 155 Mbps OTMs ... more The failure and yield on the preliminary result of our pioneer fabrication line of 155 Mbps OTMs adopting a modern Si V-groove and FCB techniques have been studied. The yields of LD purge, sub-module assembly, and final assembly were found to be 78%, 95%, and 77% respectively out of total 319 samples. The yield of whole fabrication process has been found to be 57%, where it can be improved to be 70% or higher by replacing the electrical component assembly process with more advanced IC process.
The purpose of this work is to develop an accurate non-contacting displacement sensor for use in ... more The purpose of this work is to develop an accurate non-contacting displacement sensor for use in industrial environments. The accurate measurement of small displacements is important for many industrial process applications such as lumber sawing, paper production and robot position sensing. A simple technique for the measurement of small displacements has been developed using semiconductor diode lasers in a heterodyne laser ranging system. Two collimated diode lasers are directly amplitude modulated at fm and fm + fb where fm is 10- 300 MHz and fb is 10- 50 KHz. One laser beam is reflected off the target and focused onto a detector along with the other (local oscillator) laser beam. A heterodyne signal at the beat frequency (fb) is produced. Small displacements cause a phase shift between the local oscillator signal and the collected signal from the target. Displacement sensing accuracies of 1.4 um and 50 nm have been calculated and measured over dynamic ranges of 3.5 m and 1 cm for fm = 10 MHz and 300 MHz, respectively. It has been shown that using heterodyne laser ranging with diode lasers is an accurate displacement measurement technique for industrial applications.
MOSFET degradation due to hot carrier injection is the most important reliability issue in realiz... more MOSFET degradation due to hot carrier injection is the most important reliability issue in realizing submicron ultralarge scaled integrated circuits. This degradation has been widely studied and lifetime simulators have also been developed for digital circuit operation [1]-[2]. On the other hand, the degradation of analog device parameters such as drain conductance due to hot carrier injection are not clearly understood and modeled. In this paper, we propose, for the first time, a physical model of analog drain conductance, gd degradation based on mobility reduction due to hot carrier generated interface states and show a reliability design guideline for analog devices.
Proceedings of the 5th Electronics Packaging Technology Conference (EPTC 2003)
Failure mechanisms in plastic packaged optocouplers have been investigated. The high failure rate... more Failure mechanisms in plastic packaged optocouplers have been investigated. The high failure rate of the optocouplers, specifically the reverse bias leakage current of the light emitting diodes (LEDs), was found to be moisturerelated. Using scanning electron microscopy coupled with energy dispersive X-ray microanalysis, a significant concentration of copper was detected on the surface of failed LEDs, possibly migrated from the copper leadframe. By applying infra-red photoemmision microscopy it was found that bandgap emission was associated with the reverse leakage path in the area of the pn junction of the LEDs.
2008 15th International Symposium on the Physical and Failure Analysis of Integrated Circuits, 2008
Failure mechanisms of light emitting diodes (LEDs) have been investigated. Various failure patter... more Failure mechanisms of light emitting diodes (LEDs) have been investigated. Various failure patterns of LEDs for general lighting applications were simulated under high electrical and thermal stress test conditions. Using scanning electron microscopy related with I-V characterization before and after the stress simulation, a representative failure pattern of LEDs matrixed in terms of the electrical parameter shifts and physical conditions observed after decapsulation. By applying photo-emission microscopy it was found that local damage of LED surface was caused by excessive high temperature in the area of the pn junction of LEDs.
Lasers and Electro-Optics Society, IEEE LEOS Annual Meeting, 1995
In this paper, low PWS (post-weld shift) and large aligning tolerance DFB-LD (distributed feedbac... more In this paper, low PWS (post-weld shift) and large aligning tolerance DFB-LD (distributed feedback laser diode) modules and APD (avalanche photodiode) modules were obtained by combining proper package design and the development of a laser welding technique. The welded parts of the modules were analyzed in terms of laser welding parameters, cross-section analysis and shear strength tests
ABSTRACT A novel reliability projection model of semiconductor laser diodes (LD) is presented. By... more ABSTRACT A novel reliability projection model of semiconductor laser diodes (LD) is presented. By correlating initial thermal characteristics and long-term degradation, a relationship between LD degradation and ambient temperature has been investigated. The proposed model is found to be efficient for the reliability projection of LDs, which requires a thermal characterization only at t=0
Technical Digest. CLEO/Pacific Rim '99. Pacific Rim Conference on Lasers and Electro-Optics (Cat. No.99TH8464)
Conventionally, optical communication modules for subscriber have been composed of transmitter an... more Conventionally, optical communication modules for subscriber have been composed of transmitter and receiver as separated or combined requiring two lines of optical fibers to constitute a network. To realize the fiber-to-the-home (FTTH), it is necessary to make the cheaper and more compact module as well as to reduce the fiber installation cost. In this study, an accurate silicon optical bench (SiOB) has been designed for passive integration of bidirectional transceiver sub-module. Optical coupling between the transceiver chip and a single mode fiber is accomplished by aligning an acute angle-faceted fiber on the V-groove of SiOB to the front facet of the flip-chip bonded chip. Transmitted light from the laser diode of the transceiver chip is coupled into fiber core as in usual buff coupling, while receiving light from the fiber is refracted downward by Snell's law and absorbed into pin-PD's photosensitive area after being reflected at the metal coated V-groove side-wall
Using a specifically designed test structure applying human body model electrostatic discharge (E... more Using a specifically designed test structure applying human body model electrostatic discharge (ESD) stress, the origin of dielectric breakdown in Cu/low-κ interconnect systems was found to be in interfacial delamination. The interfacial delamination between a SiC capping layer and a SiOC interdielectric layer is responsible for the increase of intermetal dielectric leakage current, causing high current Joule heating as well
In this letter, we report the high performance GaNbased light-emitting diodes (LEDs) with embedde... more In this letter, we report the high performance GaNbased light-emitting diodes (LEDs) with embedded air void array grown by metal-organic chemical vapor deposition. The donut-shaped air void was formed at the interface between crown-shaped patterned sapphire substrates (CPSS) and the GaN epilayer by conventional photolithography. The transmission electron microscopy images demonstrate that the threading dislocations were significantly suppressed by epitaxial lateral overgrowth (ELOG). The Monte Carlo ray-tracing simulation reveals that the light extraction of the air-voids embedded LED was dramatically increased due to a strong light reflection and redirection by the air voids.
Proceedings 1993 International Workshop on Vlsi Process and Device Modeling, May 14, 1993
MOSFET degradation due to hot carrier injection is the most important reliability issue in realiz... more MOSFET degradation due to hot carrier injection is the most important reliability issue in realizing submicron ultralarge scaled integrated circuits. This degradation has been widely studied and lifetime simulators have also been developed for digital circuit operation [1]-[2]. On the other hand, the degradation of analog device parameters such as drain conductance due to hot carrier injection are not clearly understood and modeled. In this paper, we propose, for the first time, a physical model of analog drain conductance, gd degradation based on mobility reduction due to hot carrier generated interface states and show a reliability design guideline for analog devices.
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