Gouri Kar - Academia.edu (original) (raw)

Papers by Gouri Kar

We use three-terminal magnetic tunnel junctions (MTJs) designed for field-free switching by spin-... more We use three-terminal magnetic tunnel junctions (MTJs) designed for field-free switching by spin-orbit torques (SOTs) to systematically study the impact of dual voltage pulses on the switching performances. We show that the concurrent action of an SOT pulse and an MTJ bias pulse allows for reducing the critical switching energy below the level typical of spin transfer torque while preserving the ability to switch the MTJ on the sub-ns time scale. By performing dc and real-time electrical measurements, we discriminate and quantify three effects arising from the MTJ bias: the voltagecontrolled change of the perpendicular magnetic anisotropy, current-induced heating, and the spin transfer torque. The experimental results are supported by micromagnetic modeling. We observe that, depending on the pulse duration and the MTJ diameter, different effects take a lead in assisting the SOTs in the magnetization reversal process. Finally, we present a compact model that allows for evaluating the...

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Solid-State Electronics, 2001

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Proceedings of SPIE - The International Society for Optical Engineering

Si/Si1-x-yGexCy/Si quantum well heterostructures grown by UHVCVD have been characterized in terms... more Si/Si1-x-yGexCy/Si quantum well heterostructures grown by UHVCVD have been characterized in terms of structural and optical properties. The Schottky barrier height (SBH) and ideality factor of PtSi/p-Si1-x-yGexCy/Si diodes have been investigated using the current-voltage characteristics. The valence band offsets of Si/Si0.795Ge0.2C0.005 and Si/Si0.79Ge0.2C0.01 have been extracted using the Schottky diode measurements. A lower value of SBH has been observed in the ternary alloy compared to those in fully strained-Si1-xGex films indicating the potential of former for long wavelength IR detection.

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Proceedings of the 21th International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA), 2014

ABSTRACT In this paper we review a dynamic device model for filamentary RRAM in HfO-based dielect... more ABSTRACT In this paper we review a dynamic device model for filamentary RRAM in HfO-based dielectrics. We summarize its transient modeling features and its statistical properties. The model explains with satisfactory quantitative resolution all main features of the RRAM switching, not just the voltage, time and temperature dependence, but also statistical fluctuations resulting from atomistic motion and their resulting LRS and HRS-distributions.

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ECS Solid State Letters, 2012

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2012 IEEE International Integrated Reliability Workshop Final Report, 2012

ABSTRACT We review our recent work on modeling of low current filamentary switching in amorphous ... more ABSTRACT We review our recent work on modeling of low current filamentary switching in amorphous HfO2 RRAM. The conduction is controlled by the width of the constriction, determining the electron transmission. The set and reset processes are modeled as a dynamic flow between two oxygen vacancy reservoirs connected by a narrow constriction. Reset is described as a dynamic balance between an upward and downward vacancy flow, while the set process is modeled as an unbalanced filament growth bounded by the external compliance. In the framework of this model, we discuss the intrinsic instabilities of narrow filamentary conduction that give rise to a series of reliability issue such as disturb and endurance. We explore some possible routes for improving the reliability.

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2012 Symposium on VLSI Technology (VLSIT), 2012

ABSTRACT An analytic dynamic hour glass model for HfO2 RRAM is demonstrated, describing the reset... more ABSTRACT An analytic dynamic hour glass model for HfO2 RRAM is demonstrated, describing the reset as a dynamic equilibrium process and the set as a constriction growth limited by ion mobility and current compliance. The dependence on time, voltage and forming conditions is in good constriction growth agreement with experiments. Since the model is fully analytical, it can be implemented in a circuit simulator.

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2013 5th IEEE International Memory Workshop, 2013

ABSTRACT We report on the performance and reliability of the Hf/HfO2 RRAM cell with Ultra-Thin Ox... more ABSTRACT We report on the performance and reliability of the Hf/HfO2 RRAM cell with Ultra-Thin Oxide (UTO-RRAM). We show that cells with an oxide thickness of 3 nm have basic performance (including speed, switching voltages, and the on/off window) similar to that of the cells with reference oxide (5-10 nm thickness), while their operation requires a forming step at a voltage of only about 1.5 V for a 40 nm size. This performance can be further optimized by tuning the cap layer thickness. We also demonstrate endurance of at least 108 cy and observe failure modes similar to the reference cells. Endurance optimization needs to take into account, next to the stack structure and pulse characteristics, the target on/off states. UTO-RRAM retention is strongly temperature-activated, with a median cell extrapolating at 125°C/10 yr. Furthermore, we analyze in detail the on-state loss and show how emergence of tail bits relates to the strength (initial level) of the state.

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Proceedings of Technical Program of 2012 VLSI Technology, System and Application, 2012

ABSTRACT Forming current Iform is a crucial parameter for stable cycling in a HfO2 RRAM stack. (i... more ABSTRACT Forming current Iform is a crucial parameter for stable cycling in a HfO2 RRAM stack. (i) Too low Iform results in constriction ‘elongation’ for filament current reduction during reset, quickly leading to failure. (ii) Too high and unlimited Iform leads to poor control of the filament nature expressed as a wide V0-distribution in the QPC model. (iii) In between, Iform is directly correlated to the minimal achievable HRS current and a narrow, stable filament is formed which allows for device scaling as well as multi-level programming.

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ECS Transactions, 2013

ABSTRACT In this work, the influence of Hf cap thickness of bipolar resistive switching in TiN\Hf... more ABSTRACT In this work, the influence of Hf cap thickness of bipolar resistive switching in TiN\HfO2\Hf\TiN resistive random access memory (RRAM) stack was investigated. More stable bipolar switching and longer endurance were achieved by increasing the Hf cap thickness from 2nm to 10nm. First-principle simulation suggested more oxygen vacancies (V-ox) generation for thicker Hf cap. Lower FORMING voltage from thicker Hf cap devices confirms more V-ox generation in the stack. X-ray photoelectron spectroscopy (XPS) also physically detected more oxygen scavenge from HfO2 bulk by thicker Hf cap. The more generated V-ox in thicker Hf cap stack probably accounted for the improved bipolar switching properties.

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2013 5th IEEE International Memory Workshop, 2013

ABSTRACT In this work, we present a systematic electrical characterization of TiNHfO2HfTiN RRAM e... more ABSTRACT In this work, we present a systematic electrical characterization of TiNHfO2HfTiN RRAM elements from the variability perspective. Variability of both programmed resistance values and switching triggering voltages has been evaluated on small scaled cells in a wide operating current range (2μA till 500μA's), for different oxide stacks, in DC and pulsed conditions. For the first time device-to-device and cycle-to-cycle variability are thoroughly compared as well as the impact of different oxygen vacancy profiles. Increase of variability in low current operation is also elucidated.

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2011 International Electron Devices Meeting, 2011

We report on world's smallest HfO2-based ... more We report on world's smallest HfO2-based Resistive RAM (RRAM) cell to date, featuring a novel Hf/HfOx resistive element stack, with an area of less than 10×10 nm2, fast ns-range on/off switching times at low-voltages and with a switching energy per bit of <0.1pJ. With excellent endurance of more than 5.107cycles, large on/off verified-window (>50), no closure of the on/off window

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MRS Proceedings, 2002

Nickel silicides were formed on Si (100) substrates and CVD grown Si0.9Ge0.1/Si layers by low the... more Nickel silicides were formed on Si (100) substrates and CVD grown Si0.9Ge0.1/Si layers by low thermal budget annealing of evaporated Ni films to evaluate their utility for ultra shallow junctions. The phase formation and microstructure of silicides formed using conventional furnace and rapid thermal annealing were studied by x-ray diffraction, Rutherford backscattering (RBS), x-ray photoelectron spectroscopy (XPS) and atomic force microscopy. RBS simulations and XPS study revealed the formation of a ternary nickel germanosilicide phase for the SiGe alloy. The incorporation of Ge resulted in a higher temperature window for the stability of low- resistive monosilicide phase. Electrical properties of the grown silicides were characterized by four-probe resistivity and contact resistance measurements.

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IEEE International Interconnect Technology Conference, 2014

ABSTRACT The scaling challenges of STT-MRAM read operation down to sub-20nm is discussed. Various... more ABSTRACT The scaling challenges of STT-MRAM read operation down to sub-20nm is discussed. Various contributing factors to the MTJ cell resistance variation were investigated with focus on MRAM cell variation due to lithography patterning technique and interconnects. With EUV SADP or single print process, the MRAM cell size can be scaled down to 18nm physical dimension with 4.2% sigma/ave cell area variation. For interconnects, the increasing resistance variation with shrinking dimensions poses most of the challenges.

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2012 International Electron Devices Meeting, 2012

ABSTRACT Bipolar switching transition metal-oxide (TMO) RRAM devices are intensively studied as p... more ABSTRACT Bipolar switching transition metal-oxide (TMO) RRAM devices are intensively studied as possible non-volatile memory for 1x nm node. HfO2 based stacks with excellent operation, good endurance and retention have been proposed [1, 2, 3], with demonstrated scalability down to

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IEEE Transactions on Magnetics, 2014

ABSTRACT The effect of four different seed layers-Ru, Hf/Ru, Ru/Hf, and Hf on the magnetic proper... more ABSTRACT The effect of four different seed layers-Ru, Hf/Ru, Ru/Hf, and Hf on the magnetic properties of [Co 5/Pt 3 Å] multilayer (ML) stack with perpendicular magnetic anisotropy was investigated. The structural quality of the ML stacks was studied and correlated with the magnetic properties. Among the abovementioned seed layers, Ru promotes stronger fcc (111) texture in the ML due to less lattice mismatch (8% between Ru and Co) in Co/Pt MLs. As a result, higher anisotropy field (HK ~ 17 kOe) and larger effective perpendicular anisotropy (Keff ~ 1.2 × 107 erg/cm3) were achieved for the MLs on Ru seed layer compared with other seed layers after annealing at 300 °C for 30 min. The perpendicular magnetic anisotropy of the MLs is improved at higher annealing temperature up to 400 °C for Ru and Hf/Ru seed layer. For the Co/Pt MLs on Ru, 1.3 × 107 erg/cm3 perpendicular magnetic anisotropy was obtained even after annealing at 400 °C. Detail investigations of postannealing stability of the ML films on different seed layers were also discussed. The magnetic properties and structural properties of the films on four different seed layers were characterized after rapid thermal annealing process at 300 °C, 350 °C, and 400 °C for 30 min annealing duration. The high temperature endurance limit up to 400 °C for 30 min of the Co/Pt MLs on Ru and Hf/Ru seed layers makes them compatible with the back-end-of-line process temperature.

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2013 IEEE International Electron Devices Meeting, 2013

ABSTRACT One of the key concerns related to low operating current (<;50μA) of RRAM is the ... more ABSTRACT One of the key concerns related to low operating current (<;50μA) of RRAM is the degraded data retention. Most of the retention studies so far focused on high switching current range. In this work, we investigate the retention degradation mechanism at low programming current range (10-40μA) and identify the key parameters that control retention in oxygen vacancy filamentary switching HfO<;sub>2<;/sub>/Hf 1T1R RRAM cells. Based on this understanding we demonstrated significant improvement in retention by adding an additional thermal budget into our process flow. The impact of the Forming process on retention property was also investigated and Forming/SET conditions were optimized to improve the retention without increasing the operation current.

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Solid-State Electronics, 2005

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Semiconductor Science and Technology, 2002

Partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterojunction p-MOSFET devices have been u... more Partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterojunction p-MOSFET devices have been used to calculate the hole mobility in buried SiGeC channels and to estimate the dominant scattering mechanisms in the carbon-containing Si alloy. The current contribution of the buried SiGeC channel to the total drain current has been found by using a simple analysis based on the inversion layer mobility model. The

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Semiconductor Science and Technology, 2002

We have fabricated p-type metal–oxide semiconductor field-effect transistor (p-MOSFET) devices wi... more We have fabricated p-type metal–oxide semiconductor field-effect transistor (p-MOSFET) devices with channel lengths from 0.8–10 μm on strained Si/Si0.8Ge0.2/Si and partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterolayers. The device characteristics, the source–drain resistance and the mobility degradation factor have been studied for control-Si, Si0.8Ge0.2 and Si0.793Ge0.2C0.007 devices over the temperature range of 300–77 K. Though a significant improvement in the drive current

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We use three-terminal magnetic tunnel junctions (MTJs) designed for field-free switching by spin-... more We use three-terminal magnetic tunnel junctions (MTJs) designed for field-free switching by spin-orbit torques (SOTs) to systematically study the impact of dual voltage pulses on the switching performances. We show that the concurrent action of an SOT pulse and an MTJ bias pulse allows for reducing the critical switching energy below the level typical of spin transfer torque while preserving the ability to switch the MTJ on the sub-ns time scale. By performing dc and real-time electrical measurements, we discriminate and quantify three effects arising from the MTJ bias: the voltagecontrolled change of the perpendicular magnetic anisotropy, current-induced heating, and the spin transfer torque. The experimental results are supported by micromagnetic modeling. We observe that, depending on the pulse duration and the MTJ diameter, different effects take a lead in assisting the SOTs in the magnetization reversal process. Finally, we present a compact model that allows for evaluating the...

Bookmarks Related papers MentionsView impact

Solid-State Electronics, 2001

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Proceedings of SPIE - The International Society for Optical Engineering

Si/Si1-x-yGexCy/Si quantum well heterostructures grown by UHVCVD have been characterized in terms... more Si/Si1-x-yGexCy/Si quantum well heterostructures grown by UHVCVD have been characterized in terms of structural and optical properties. The Schottky barrier height (SBH) and ideality factor of PtSi/p-Si1-x-yGexCy/Si diodes have been investigated using the current-voltage characteristics. The valence band offsets of Si/Si0.795Ge0.2C0.005 and Si/Si0.79Ge0.2C0.01 have been extracted using the Schottky diode measurements. A lower value of SBH has been observed in the ternary alloy compared to those in fully strained-Si1-xGex films indicating the potential of former for long wavelength IR detection.

Bookmarks Related papers MentionsView impact

Proceedings of the 21th International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA), 2014

ABSTRACT In this paper we review a dynamic device model for filamentary RRAM in HfO-based dielect... more ABSTRACT In this paper we review a dynamic device model for filamentary RRAM in HfO-based dielectrics. We summarize its transient modeling features and its statistical properties. The model explains with satisfactory quantitative resolution all main features of the RRAM switching, not just the voltage, time and temperature dependence, but also statistical fluctuations resulting from atomistic motion and their resulting LRS and HRS-distributions.

Bookmarks Related papers MentionsView impact

ECS Solid State Letters, 2012

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2012 IEEE International Integrated Reliability Workshop Final Report, 2012

ABSTRACT We review our recent work on modeling of low current filamentary switching in amorphous ... more ABSTRACT We review our recent work on modeling of low current filamentary switching in amorphous HfO2 RRAM. The conduction is controlled by the width of the constriction, determining the electron transmission. The set and reset processes are modeled as a dynamic flow between two oxygen vacancy reservoirs connected by a narrow constriction. Reset is described as a dynamic balance between an upward and downward vacancy flow, while the set process is modeled as an unbalanced filament growth bounded by the external compliance. In the framework of this model, we discuss the intrinsic instabilities of narrow filamentary conduction that give rise to a series of reliability issue such as disturb and endurance. We explore some possible routes for improving the reliability.

Bookmarks Related papers MentionsView impact

2012 Symposium on VLSI Technology (VLSIT), 2012

ABSTRACT An analytic dynamic hour glass model for HfO2 RRAM is demonstrated, describing the reset... more ABSTRACT An analytic dynamic hour glass model for HfO2 RRAM is demonstrated, describing the reset as a dynamic equilibrium process and the set as a constriction growth limited by ion mobility and current compliance. The dependence on time, voltage and forming conditions is in good constriction growth agreement with experiments. Since the model is fully analytical, it can be implemented in a circuit simulator.

Bookmarks Related papers MentionsView impact

2013 5th IEEE International Memory Workshop, 2013

ABSTRACT We report on the performance and reliability of the Hf/HfO2 RRAM cell with Ultra-Thin Ox... more ABSTRACT We report on the performance and reliability of the Hf/HfO2 RRAM cell with Ultra-Thin Oxide (UTO-RRAM). We show that cells with an oxide thickness of 3 nm have basic performance (including speed, switching voltages, and the on/off window) similar to that of the cells with reference oxide (5-10 nm thickness), while their operation requires a forming step at a voltage of only about 1.5 V for a 40 nm size. This performance can be further optimized by tuning the cap layer thickness. We also demonstrate endurance of at least 108 cy and observe failure modes similar to the reference cells. Endurance optimization needs to take into account, next to the stack structure and pulse characteristics, the target on/off states. UTO-RRAM retention is strongly temperature-activated, with a median cell extrapolating at 125°C/10 yr. Furthermore, we analyze in detail the on-state loss and show how emergence of tail bits relates to the strength (initial level) of the state.

Bookmarks Related papers MentionsView impact

Proceedings of Technical Program of 2012 VLSI Technology, System and Application, 2012

ABSTRACT Forming current Iform is a crucial parameter for stable cycling in a HfO2 RRAM stack. (i... more ABSTRACT Forming current Iform is a crucial parameter for stable cycling in a HfO2 RRAM stack. (i) Too low Iform results in constriction ‘elongation’ for filament current reduction during reset, quickly leading to failure. (ii) Too high and unlimited Iform leads to poor control of the filament nature expressed as a wide V0-distribution in the QPC model. (iii) In between, Iform is directly correlated to the minimal achievable HRS current and a narrow, stable filament is formed which allows for device scaling as well as multi-level programming.

Bookmarks Related papers MentionsView impact

ECS Transactions, 2013

ABSTRACT In this work, the influence of Hf cap thickness of bipolar resistive switching in TiN\Hf... more ABSTRACT In this work, the influence of Hf cap thickness of bipolar resistive switching in TiN\HfO2\Hf\TiN resistive random access memory (RRAM) stack was investigated. More stable bipolar switching and longer endurance were achieved by increasing the Hf cap thickness from 2nm to 10nm. First-principle simulation suggested more oxygen vacancies (V-ox) generation for thicker Hf cap. Lower FORMING voltage from thicker Hf cap devices confirms more V-ox generation in the stack. X-ray photoelectron spectroscopy (XPS) also physically detected more oxygen scavenge from HfO2 bulk by thicker Hf cap. The more generated V-ox in thicker Hf cap stack probably accounted for the improved bipolar switching properties.

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2013 5th IEEE International Memory Workshop, 2013

ABSTRACT In this work, we present a systematic electrical characterization of TiNHfO2HfTiN RRAM e... more ABSTRACT In this work, we present a systematic electrical characterization of TiNHfO2HfTiN RRAM elements from the variability perspective. Variability of both programmed resistance values and switching triggering voltages has been evaluated on small scaled cells in a wide operating current range (2μA till 500μA's), for different oxide stacks, in DC and pulsed conditions. For the first time device-to-device and cycle-to-cycle variability are thoroughly compared as well as the impact of different oxygen vacancy profiles. Increase of variability in low current operation is also elucidated.

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2011 International Electron Devices Meeting, 2011

We report on world's smallest HfO2-based ... more We report on world's smallest HfO2-based Resistive RAM (RRAM) cell to date, featuring a novel Hf/HfOx resistive element stack, with an area of less than 10×10 nm2, fast ns-range on/off switching times at low-voltages and with a switching energy per bit of <0.1pJ. With excellent endurance of more than 5.107cycles, large on/off verified-window (>50), no closure of the on/off window

Bookmarks Related papers MentionsView impact

MRS Proceedings, 2002

Nickel silicides were formed on Si (100) substrates and CVD grown Si0.9Ge0.1/Si layers by low the... more Nickel silicides were formed on Si (100) substrates and CVD grown Si0.9Ge0.1/Si layers by low thermal budget annealing of evaporated Ni films to evaluate their utility for ultra shallow junctions. The phase formation and microstructure of silicides formed using conventional furnace and rapid thermal annealing were studied by x-ray diffraction, Rutherford backscattering (RBS), x-ray photoelectron spectroscopy (XPS) and atomic force microscopy. RBS simulations and XPS study revealed the formation of a ternary nickel germanosilicide phase for the SiGe alloy. The incorporation of Ge resulted in a higher temperature window for the stability of low- resistive monosilicide phase. Electrical properties of the grown silicides were characterized by four-probe resistivity and contact resistance measurements.

Bookmarks Related papers MentionsView impact

IEEE International Interconnect Technology Conference, 2014

ABSTRACT The scaling challenges of STT-MRAM read operation down to sub-20nm is discussed. Various... more ABSTRACT The scaling challenges of STT-MRAM read operation down to sub-20nm is discussed. Various contributing factors to the MTJ cell resistance variation were investigated with focus on MRAM cell variation due to lithography patterning technique and interconnects. With EUV SADP or single print process, the MRAM cell size can be scaled down to 18nm physical dimension with 4.2% sigma/ave cell area variation. For interconnects, the increasing resistance variation with shrinking dimensions poses most of the challenges.

Bookmarks Related papers MentionsView impact

2012 International Electron Devices Meeting, 2012

ABSTRACT Bipolar switching transition metal-oxide (TMO) RRAM devices are intensively studied as p... more ABSTRACT Bipolar switching transition metal-oxide (TMO) RRAM devices are intensively studied as possible non-volatile memory for 1x nm node. HfO2 based stacks with excellent operation, good endurance and retention have been proposed [1, 2, 3], with demonstrated scalability down to

Bookmarks Related papers MentionsView impact

IEEE Transactions on Magnetics, 2014

ABSTRACT The effect of four different seed layers-Ru, Hf/Ru, Ru/Hf, and Hf on the magnetic proper... more ABSTRACT The effect of four different seed layers-Ru, Hf/Ru, Ru/Hf, and Hf on the magnetic properties of [Co 5/Pt 3 Å] multilayer (ML) stack with perpendicular magnetic anisotropy was investigated. The structural quality of the ML stacks was studied and correlated with the magnetic properties. Among the abovementioned seed layers, Ru promotes stronger fcc (111) texture in the ML due to less lattice mismatch (8% between Ru and Co) in Co/Pt MLs. As a result, higher anisotropy field (HK ~ 17 kOe) and larger effective perpendicular anisotropy (Keff ~ 1.2 × 107 erg/cm3) were achieved for the MLs on Ru seed layer compared with other seed layers after annealing at 300 °C for 30 min. The perpendicular magnetic anisotropy of the MLs is improved at higher annealing temperature up to 400 °C for Ru and Hf/Ru seed layer. For the Co/Pt MLs on Ru, 1.3 × 107 erg/cm3 perpendicular magnetic anisotropy was obtained even after annealing at 400 °C. Detail investigations of postannealing stability of the ML films on different seed layers were also discussed. The magnetic properties and structural properties of the films on four different seed layers were characterized after rapid thermal annealing process at 300 °C, 350 °C, and 400 °C for 30 min annealing duration. The high temperature endurance limit up to 400 °C for 30 min of the Co/Pt MLs on Ru and Hf/Ru seed layers makes them compatible with the back-end-of-line process temperature.

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2013 IEEE International Electron Devices Meeting, 2013

ABSTRACT One of the key concerns related to low operating current (<;50μA) of RRAM is the ... more ABSTRACT One of the key concerns related to low operating current (<;50μA) of RRAM is the degraded data retention. Most of the retention studies so far focused on high switching current range. In this work, we investigate the retention degradation mechanism at low programming current range (10-40μA) and identify the key parameters that control retention in oxygen vacancy filamentary switching HfO<;sub>2<;/sub>/Hf 1T1R RRAM cells. Based on this understanding we demonstrated significant improvement in retention by adding an additional thermal budget into our process flow. The impact of the Forming process on retention property was also investigated and Forming/SET conditions were optimized to improve the retention without increasing the operation current.

Bookmarks Related papers MentionsView impact

Solid-State Electronics, 2005

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Semiconductor Science and Technology, 2002

Partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterojunction p-MOSFET devices have been u... more Partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterojunction p-MOSFET devices have been used to calculate the hole mobility in buried SiGeC channels and to estimate the dominant scattering mechanisms in the carbon-containing Si alloy. The current contribution of the buried SiGeC channel to the total drain current has been found by using a simple analysis based on the inversion layer mobility model. The

Bookmarks Related papers MentionsView impact

Semiconductor Science and Technology, 2002

We have fabricated p-type metal–oxide semiconductor field-effect transistor (p-MOSFET) devices wi... more We have fabricated p-type metal–oxide semiconductor field-effect transistor (p-MOSFET) devices with channel lengths from 0.8–10 μm on strained Si/Si0.8Ge0.2/Si and partially strain compensated Si/Si0.793Ge0.2C0.007/Si heterolayers. The device characteristics, the source–drain resistance and the mobility degradation factor have been studied for control-Si, Si0.8Ge0.2 and Si0.793Ge0.2C0.007 devices over the temperature range of 300–77 K. Though a significant improvement in the drive current

Bookmarks Related papers MentionsView impact