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Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 mu s (mean 33.3 mu s) for the ocular myasthenia gravis and from 14.4 to 220.4 mu s (mean 66.3 mu s) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 mu s (mean 33.3 mu s) for the ocular myasthenia gravis and from 14.4 to 220.4 mu s (mean 66.3 mu s) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 mu s (mean 33.3 mu s) for the ocular myasthenia gravis and from 14.4 to 220.4 mu s (mean 66.3 mu s) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 mu s (mean 33.3 mu s) for the ocular myasthenia gravis and from 14.4 to 220.4 mu s (mean 66.3 mu s) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

Objectives: To estimate the jitter parameters (single-fiber electromyography) in myasthenia gravis patients mostly by electrical activation in Frontalis, Orbicularis Oculi, and Extensor Digitorum muscles using a concentric needle electrode. Methods: Between 2009 and 2019, a total of 97 myasthenia gravis patients, 52 male, and mean age 54 years were included. Results: Any abnormal jitter parameter in individual muscles was 90.5% (Frontalis), 88.5% (Orbicularis Oculi), and 86.6% (Extensor Digitorum). Any jitter parameter combining Orbicularis Oculi and Frontalis muscle was abnormal in 100% for the ocular, and in 92.9% for the generalized myasthenia gravis. The most abnormal muscle was Orbicularis Oculi for the generalized, and Frontalis for the ocular myasthenia gravis. The decrement was abnormal in 78.4%, 85.9% for the generalized, and 25% for the ocular myasthenia gravis. The mean jitter ranged from 14.2 to 86 mu s (mean 33.3 mu s) for the ocular myasthenia gravis and from 14.4 to 220.4 mu s (mean 66.3 mu s) for the generalized myasthenia gravis. The antibody titers tested positive in 86.6%, 91.8% for the generalized, and 50% for the ocular myasthenia gravis. Thymectomy was done in 48.5%, thymoma was found in 19.6%, and myasthenic crisis occurred by 21.6%. Conclusion: The jitter parameters achieved a 100% abnormality in ocular myasthenia gravis if both the Orbicularis Oculi and Frontalis muscles were tested. There was a high jitter abnormality in generalized myasthenia gravis cases with one muscle tested, with about a 2% increase in sensitivity when a second is added. Concentric needle electrode jitter had high sensitivity similar to the single fiber electrode (93.8%), followed by antibody titers (86.6%), and abnormal decrement (78.4%).

We have investigated in-diffusion of phosphorus into monocrystalline silicon by depositing a phosphorus source on the surface followed by millisecond flash lamp annealing (FLA) to form shallow emitters for solar cells. By varying both the energy density of a 20 ms flash in the range from 62 to 132 J/cm(2) and the sample preheating, it is observed that FLA treatments can in-diffuse a high concentration of phosphorus atoms becoming electrically active. The most promising emitters are obtained after FLA in the energy range from 110 to 128 J/cm(2) including preheating at 300 degrees C with a peak concentration of 4 - 6 x 10(20) cm(-3). The emitter junction depth for these treatments is in the range of 100 nm to 200 nm, respectively.

A post implantation microwave annealing technique has been used for the electrical activation of Al + implanted ions in semi-insulating 4H-SiC. The annealing temperatures have been 2000-2100°C. The implanted Al concentration has been varied from 5 × 10 19 to 8 × 10 20 cm -3. A minimum resistivity of 2 × 10 -2 Ω·cm and about 70% electrical activation of the implanted Al has been measured at room temperature for an implanted Al concentration of 8 × 10 20 cm -3 and a microwave annealing at 2100°C for 30s., QC 20120807

Heavily p-type doped Ge layers were fabricated by 100 keV Ga implantation and subsequent flash lamp annealing for 3 ms in the temperature range between 700°C and 900°C. For comparison some samples were annealed in a rapid thermal processor for 60 s. Ga fluences of 2x1015cm-2, 6x1015cm-2 and 2x1016cm-2 were chosen in order to achieve Ga peak concentrations ranging from values slightly below the equilibrium solid solubility limit of 4.9x1020 cm-3 up to 3.5x1021 cm-3 which corresponds to a maximum Ga content of about 8 at-%. The structure of the doped layer and the Ga distribution were investigated by Rutherford backscattering spectrometry in combination with ion channelling, cross-sectional electron microscopy and secondary ion mass spectrometry. Temperature dependent Hall effect measurements were carried out in order to determine the electrical properties of the Ga doped layers. It is shown that by flash lamp annealing Ga diffusion into the bulk can be completely avoided and the Ga loss by outdiffusion from the surface is reduced. The lowest sheet resistances of 36 Ohm/sq. was achieved for the medium Ga concentration annealed at 900°C. The best Ga activation values are 73%, 60% and 24% for the three Ga fluences under investigation. The Ga activation is correlated with the layer regrowth. Incomplete epitaxial regrowth as observed in some samples leads to lower activation.

Shallow n+ layers in Ge are formed by phosphorus implantation and subsequent millisecond flash lamp annealing. Present investigations are focused on the dependence of P redistribution, diffusion and electrical activation on heat input into the sample and flash duration. Furthermore, the influence of pre-amorphization implantation and pre-annealing is studied. In contrast to conventional annealing procedures an activation up to 6.5×1019 cm-3 is achieved without any dopant redistribution and noticeable diffusion. Present results suggest that independently of pre-treatment the maximum activation should be obtained at a flash energy that corresponds to the onset of P diffusion. The deactivation of P is explained qualitatively by mass action analysis which takes into account the formation of phosphorus-vacancy clusters.

We present experimental results on the activation and diffusion behaviors of boron in silicon-on-insulator and strained silicon-on-insulator using standard rapid thermal processing treatments as well as flash lamp annealing. After boron implantation at different doses and at a low energy of 1 keV, samples were annealed to activate the dopants, and secondary ion mass spectrometry and Hall measurements were carried out to determine boron diffusion and the amount of activated dopants, respectively. In contrast to rapid thermal annealing, flash lamp annealing enables the activation without significant diffusion of dopants. In addition, we investigated the effect of coating the samples with antireflection layers to increase the absorbed energy during flash annealing. As a result, the activation was increased significantly to values comparable with the activation obtained with standard annealing. Furthermore, the relation between the observed boron diffusion and activation as a function of the implantation and annealing parameters is discussed in terms of the kinetics of the defects involved in these processes.

Ion implantation in Ge is studied at energies and doses relevant for application to advanced modern devices, such as CMOS transistors. Shallow donors like P typically have high diffusivity and low activity in view of the formation of shallow, low-resistance junctions. Similarly to the Si case, co-doping with non-dopant elements (N in this study) and advanced annealing techniques, such as FLA annealing, can provide a viable route to significantly improve the trade-off of n-type Ge junctions. Residual implant-induced defectivity, which can be a source of enhanced diffusion and generation currents in Ge diodes, seems to remain up to temperatures (≥ 500 oC) important for activation of dopants in Ge. However, once the thermal budget is optimized for implant damage removal, the Ge diode leakage may be dominated by surface generation currents, due to a high density of surface states, not efficiently reduced by current passivation schemes.

Ion implantation in Ge is studied at energies and doses relevant for application to advanced modern devices, such as CMOS transistors. Shallow donors like P typically have high diffusivity and low activity in view of the formation of shallow, low-resistance junctions. Similarly to the Si case, co-doping with non-dopant elements (N in this study) and advanced annealing techniques, such as FLA annealing, can provide a viable route to significantly improve the trade-off of n-type Ge junctions. Residual implant-induced defectivity, which can be a source of enhanced diffusion and generation currents in Ge diodes, seems to remain up to temperatures (≥ 500 oC) important for activation of dopants in Ge. However, once the thermal budget is optimized for implant damage removal, the Ge diode leakage may be dominated by surface generation currents, due to a high density of surface states, not efficiently reduced by current passivation schemes.

Ion implantation in Ge is studied at energies and doses relevant for application to advanced modern devices, such as CMOS transistors. Shallow donors like P typically have high diffusivity and low activity in view of the formation of shallow, low-resistance junctions. Similarly to the Si case, co-doping with non-dopant elements (N in this study) and advanced annealing techniques, such as FLA annealing, can provide a viable route to significantly improve the trade-off of n-type Ge junctions. Residual implant-induced defectivity, which can be a source of enhanced diffusion and generation currents in Ge diodes, seems to remain up to temperatures (≥ 500 oC) important for activation of dopants in Ge. However, once the thermal budget is optimized for implant damage removal, the Ge diode leakage may be dominated by surface generation currents, due to a high density of surface states, not efficiently reduced by current passivation schemes.

In this project we study diffusion and electrical activation in lithium and helium implanted ZnO single crystal wafers with high resistivity using secondary ion mass spectrometry (SIMS), scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM), respectively. Li+ ions were implanted with an energy of 837 keV at a dose of 2x1015 cm-2, and He+ were implanted with an energy of 683 keV at a dose of 6x1015 cm-2 to ensure similar implantation depths and damage productions. The samples were then annealed using short 20 ms light flashes corresponding to temperatures of 900°C, 1200°C and 1400°C. After each annealing step the samples were characterized with SSRM/SCM and SIMS. In as-implanted samples, no changes in the initially high resistivity are observed in neither the Li- nor the He-implanted samples but after the thermal treatments a substantial decrease is observed in both sets of samples. This resistivity drop is most likely related to electrical activation of shallow implantation-induced defects or deactivation of compensating defects/impurities, as He in principle should be electrically inactive in any solid state material. No significant redistribution of the implanted ions is observed.

We have investigated flash-lamp annealing (FLA) of germanium wafers doped with phosphorous and boron introduced in the Ge crystal by ion implantation. Annealing was performed by using pre-heating at 400-450 oC in a conventional rapid thermal processing (RTP) unit and a fast (3-20 ms) FLA annealing at 800 oC or 900 oC. Diffusion of P is suppressed during the 800oC-20 ms FLA annealing, while concentration-enhanced diffusion occurs upon 900oC FLA anneals. At this higher temperature the FLA pulse time becomes a fundamental parameter, since the shortest FLA pulse (3 ms) causes less junction deepening and less P dose loss as compared to the longest (20 ms) pulse. Importantly, P activation seems to be enhanced by the FLA process. The FLA process applied to B-doped pre-amorphized Ge layers does not show advantages as compared to a RTP conventional annealing. B diffusion and activation behavior are indeed similar for the millisecond annealing approach and for a conventional RTP combined with a solid phase epitaxial regrowth of the doped Ge layer. In summary, the FLA technique holds a potential for the development of P shallow junctions in germanium wafers. However, junction stability following the FLA process is a concern and needs to be further investigated.

In this project we study diffusion and electrical activation in lithium and helium implanted ZnO single crystal wafers with high resistivity using secondary ion mass spectrometry (SIMS), scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM), respectively. Li+ ions were implanted with an energy of 837 keV at a dose of 2x1015 cm-2, and He+ were implanted with an energy of 683 keV at a dose of 6x1015 cm-2 to ensure similar implantation depths and damage productions. The samples were then annealed using short 20 ms light flashes corresponding to temperatures of 900°C, 1200°C and 1400°C. After each annealing step the samples were characterized with SSRM/SCM and SIMS. In as-implanted samples, no changes in the initially high resistivity are observed in neither the Li- nor the He-implanted samples but after the thermal treatments a substantial decrease is observed in both sets of samples. This resistivity drop is most likely related to electrical activation of shallow implantation-induced defects or deactivation of compensating defects/impurities, as He in principle should be electrically inactive in any solid state material. No significant redistribution of the implanted ions is observed.

We have investigated flash-lamp annealing (FLA) of germanium wafers doped with phosphorous and boron introduced in the Ge crystal by ion implantation. Annealing was performed by using pre-heating at 400-450 oC in a conventional rapid thermal processing (RTP) unit and a fast (3-20 ms) FLA annealing at 800 oC or 900 oC. Diffusion of P is suppressed during the 800oC-20 ms FLA annealing, while concentration-enhanced diffusion occurs upon 900oC FLA anneals. At this higher temperature the FLA pulse time becomes a fundamental parameter, since the shortest FLA pulse (3 ms) causes less junction deepening and less P dose loss as compared to the longest (20 ms) pulse. Importantly, P activation seems to be enhanced by the FLA process. The FLA process applied to B-doped pre-amorphized Ge layers does not show advantages as compared to a RTP conventional annealing. B diffusion and activation behavior are indeed similar for the millisecond annealing approach and for a conventional RTP combined with a solid phase epitaxial regrowth of the doped Ge layer. In summary, the FLA technique holds a potential for the development of P shallow junctions in germanium wafers. However, junction stability following the FLA process is a concern and needs to be further investigated.

Electrical activation studies of silicon implanted Al(x)Ga(1-x)N grown on sapphire substrates were conducted as a function of ion dose, anneal temperature, and anneal time. Silicon ion doses of 1x10(exp 13), 5x10(exp 13), and 1x10(exp 14) /sq cm were implanted in Al(x)Ga(1-x)N samples with aluminum mole fractions of 0.1 and 0.2 at an energy of 200 keV at room temperature. The samples were proximity cap annealed at temperatures from 1100 to 1350 degrees C and anneal times of 20 to 40 minutes with a 500 thick AlN cap in a nitrogen environment. The Hall coefficient and resistivity were measured using room temperature Hall effect measurements. From this data the Hall mobility, sheet carrier concentration, and electrical activation efficiencies were calculated. Activation efficiencies of almost 100% were achieved for Al(0.2)Ga(0.8)N samples having doses of 5x10(exp 13) and 1x10(exp 14) /sq cm after annealing at 1350 and 1300 C, respectively, for 20 minutes. After annealing at 1250 C for 20 minutes, 87% efficiency was achieved for Al(0.1)Ga(0.9)N implanted with 1x10(exp 14) /sq cm silicon ions. The largest observed mobility was 89 /sq cm/V's for Al(0.1)Ga(0.9)N implanted with 1x10(exp 14) /sq cm and 5x10(exp 13) /sq cm silicon ions and annealed at 1250 degrees C for 20 minutes and at 1200 degrees C for 40 minutes, respectively. The optimal anneal condition to maximize electrical activation efficiency and minimize nitrogen dissociation damage for Al(0.1)Ga(0.9)N was 1200 C anneal for 40 minutes. The mobilities, sheet carrier concentrations, and electrical activation efficiencies generally increased., The original document contains color images.

We have studied B re-distribution in Si after excimer laser annealing (ELA) with multiple laser pulses. B was implanted using both B and BF2 ions with energies from 1 to 20 keV and doses of 1 x 10(14) and 1 x 10(15) cm(-2). ELA with the number of pulses from 1 to 100 was performed in vacuum with the sample kept at room temperature and 450 degrees C. Independently of the implantation parameters and the ELA conditions used, a peak in the B concentration is observed near the maximum melting depth after 10 pulses of ELA. A detailed study has revealed that B accumulates at the maximum melt depth gradually with the number of ELA pulses. An increase in the carrier concentration at the maximum melt depth is observed after ELA with 100 pulses. No structural defects have been detected by transmission electron microscopy in the region of the B accumulation., QC 20100525 QC 20111012

We have investigated the effect of excimer laser annealing (ELA) on transient enhanced diffusion (TED) and activation of boron implanted in Si during subsequent rapid thermal annealing (RTA). It is observed that ELA with partial melting of the implanted region causes reduction of TED in the region that remains solid during ELA, where the diffusion length of boron is reduced by a factor of similar to 4 as compared to the as-implanted sample. This is attributed to several mechanisms such as liquid-state annealing of a fraction of the implantation induced defects, introduction of excess vacancies during ELA, and solid-state annealing of the defects beyond the maximum melting depth by the heat wave propagating into the Si wafer. The ELA pretreatment provides a substantially improved electrical activation of boron during subsequent RTA., QC 20100525

We have studied B redistribution in Si after excimer laser annealing (ELA) with multiple laser pulses. B was implanted with energies of 1 and 10 keV and doses of 1x10(14) and 1x10(15) cm(-2). ELA with the number of pulses from 1 to 100 was performed at room temperature and 450 degrees C in vacuum. Irrespective of the implantation parameters and the ELA conditions used, a pile-up in the B concentration is observed near the maximum melting depth after ten pulses of ELA. Moreover, a detailed study has revealed that B accumulates at the maximum melt depth gradually with the number of ELA pulses. Besides, an increase in the carrier concentration is observed at the maximum melt depth, suggesting electrical activity of the accumulated B. Formation of Si-B complexes and vacancy accumulation during multiple ELA are discussed as possible mechanisms for the B build-up., QC 20100525

The electrical properties of high concentration aluminum and nitrogen implanted layers have been investigated after furnace as well as flash lamp annealing. For Al doped layers the electrical efficiency is enhanced using flash lamp annealing. For highest Al concentrations the doped layer shows metal like conductivity. For N doped layers the flash lamp annealing effects no increase of the carrier concentration. Due to the short annealing time only the nitrogen on hexagonal sites is electrically active. Flash lamp annealing produced no extra damage of the vacancy type as proved by Positron Annihilation Spectroscopy.

Results of an extensive study concerning implantation, annealing and electrical activation of Al and B layers of 6H-SiC are presented. With increasing implantation temperature the implantation induced damage decreased. After annealing dislocation loops are observed in Al implanted layers whereas loops and precepitates are found in B implanted layers. For good electrical properties amorphization must be avoided. Using flash lamp annealing hole concentration is measured for Al doping whereas for B doping a limited hole concentration is observed.