Technical Digest. Summaries of Papers Presented at the Conference on Lasers and Electro-Optics. Conference Edition. 1998 Technical Digest Series, Vol.6 (IEEE Cat. No.98CH36178), 1998
Summary form only given. Optical glasses show higher information density recording compared with ... more Summary form only given. Optical glasses show higher information density recording compared with the usual photomaterials. Different linear and nonlinear phenomena were used for this goal. We study a new mechanism of glass excitation leading to modification of glass optical parameters that can be used for data recording
Conference Proceedings. LEOS'98. 11th Annual Meeting. IEEE Lasers and Electro-Optics Society 1998 Annual Meeting (Cat. No.98CH36243)
We present Laue diffraction experiments using a fs laser plasma X-ray ultrashort pulse source as ... more We present Laue diffraction experiments using a fs laser plasma X-ray ultrashort pulse source as preliminary experiments for time resolved X-ray Laue diffraction. The Laue method in X-ray diffraction experiments employs an X-ray beam consisting of a range of wavelengths to illuminate a stationary crystal.
The availability of ultrashort (100 fs) high intensity lasers capable of producing focused intens... more The availability of ultrashort (100 fs) high intensity lasers capable of producing focused intensities in excess of 10{sup 18} W/cm{sup 2} provides many new opportunities in studying the interaction of radiation with matter. The authors describe a new laser plasma facility constructed around a Cr: LISAF laser system currently capable of output energies of {approximately}1J in times of {approximately}100 fs. This facility will be directed initially towards basic studies of the interaction of intense ultrashort laser pulses with dense plasmas, and the generation and application of intense hard x-ray point sources. The laser system the authors have developed for this facility, uses the new solid-state laser material, Cr:LiSAF. This material has many advantages for the generation of intense ultrashort laser pulses. The spectral gain bandwidth is sufficiently broad for the amplification of pulses shorter than 100 fs in duration. Its fluorescence lifetime is long enough to permit the use of conventional flashlamp pumping, and its emission cross-section is such that it provides a small signal gains high enough to allow its use in a high powered chirped pulsed amplification laser architectures. Modifications currently being implemented onto their Cr:LiSAF laser system include improvements to pulse contrast, energy extraction, beam uniformity andmore » focusability. The system will soon be incorporated with a 52-port precision target chamber that will be equipped with a broad array of x-ray and plasma diagnostics. Several research programs are being designed around this facility. Two of these programs, those relating to the use of hard x-rays for the analysis of shock phenomena in solids and the general physics of extremely high magnetic fields will be presented.« less
With the intent of finding a sensitive photocathode material in the 130 Å (100eV) X-ray range for... more With the intent of finding a sensitive photocathode material in the 130 Å (100eV) X-ray range for use in a high resolution soft X-ray Conversion Microscope, photoelectron yields of several materials (mostly alkali halides), were measured at the National Institute of Standards and Technology's (NIST) Synchrotron Ultraviolet Radiation Facility II (SURF II). These measurements were made as a function of wavelength in the spectral range 115 Å-400 Å. The measured values are comparable to previous measurements of the photoelectron yields of these and similar materials, and to an existing model of photoemission [1–3]. We also determined the effects of prolonged exposure to X-ray light on performance. Moreover, because of the hygroscopic nature of Alkali Iodides, measurements of the photoelectron yield versus wavelength were repeated for samples of CsI that were kept in storage for periods of time to determine the effects of storage time and water absorption on the photoelectron yield.
ABSTRACT The NIST Extreme Ultraviolet (EUV) Reflectometry Facility was designed in the 1990s to a... more ABSTRACT The NIST Extreme Ultraviolet (EUV) Reflectometry Facility was designed in the 1990s to accommodate the largest multilayer optics envisioned at that time. However, with increasing power requirements for an EUV scanner, source collection optics have grown larger and more steeply curved than the original design would allow. To accommodate these changes, the mechanical and operational parameters of the facility have been upgraded. To access the entire surface of a larger optic, an auxiliary off-axis rotation stage has been installed allowing an increase in maximum optic size from 350 mm to 450 mm. Likewise, to deal with the deeper sags and steeper slopes of these optics, we have had to significantly expand our data analysis capabilities. In order to make these measurements, the incident radiation is reflected out of the vertical plane, allowing for measurements of effectively unpolarized radiation, an advantage for EUV lithography optics such as source collectors.
ABSTRACT Currently we are commissioning a second multilayer-based beamline to study the radiation... more ABSTRACT Currently we are commissioning a second multilayer-based beamline to study the radiation hardness of multilayers under extreme-ultraviolet (EUV) irradiation in an oxidizing atmosphere. Multilayer lifetime is one of the most important issues for the commercialization of extreme-ultraviolet lithography. The beamline employs a spherical multilayer mirror and a beryllium filter. The mirror demagnifies the source and reflects 13.4 nm radiation as well as visible light. The beryllium filter suppresses the visible light reflected by the mirror and provides also a barrier between the extremely clean storage ring vacuum and the water atmosphere of the test chamber.
Journal of research of the National Institute of Standards and Technology, 2003
The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons f... more The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This region includes the M3, M4, and M5 absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well. Separately, the effects of dynamic screening were observed as shown by an atomic calculation within the relativistic time-dependent local-density approximation. Dynamic screening effects influence the spectra at the 25 % level and are observed for both tungsten and tantalum. We applied these results to characterize spatially-resolved spectra of a tungsten integrated circuit interconnect obtained using a scanning transmission x-ray microscope. The results indicate tungsten fiducial markers were deposited into silica trenches with a depths of 50 % and 60 % of the markers' heights.
The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most a... more The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most accurate method for measurement of radiant power in the extreme ultraviolet. At the National Institute of Standards and Technology, ACR-based measurements are currently used as standards from the infrared and into the vacuum ultraviolet, however, no radiometric facilities are currently in operation with enough incident power to use an ACR in the extreme-ultraviolet region. Therefore, we have installed transfer optics on an existing beamline to allow the installation of the ACR as an additional endstation. We will describe the current radiometric beamline, the ACR, and the high-throughput beamline, and the transfer-optical system. Finally, we will present the performance of the transfer optics and measurements of the beam profile and incident power of the new endstation.
ABSTRACT In this work, we discuss several parameters influencing extreme ultraviolet (EUV) resist... more ABSTRACT In this work, we discuss several parameters influencing extreme ultraviolet (EUV) resist qualification test results. The witness sample resist qualifications test is implemented on several different instruments world wide. The original protocol for the test developed by the tool manufacturer requires that a 300 mm wafer be exposed to a dose to clear in one hour. Also required is that the carbon contamination rate on the witness sample be mass limited, i.e., that the rate be saturated with respect to the EUV or e-beam intensity. Simple arguments have been presented in the past to show that the thickness of the carbon growth should be inversely proportional to the pumping speed and proportional to the area exposed if dose and duration were held constant. The present experiments demonstrate the real-life limitations of these arguments and provide validation to our area scaling procedure to equate test results done with 200 mm wafers to results expected for 300 mm wafers. In the process of studying the dependence of carbon growth on pumping speed, we encountered the important effect of increased partial pressure on the degree of intensity saturation.
Technical Digest. Summaries of Papers Presented at the Conference on Lasers and Electro-Optics. Conference Edition. 1998 Technical Digest Series, Vol.6 (IEEE Cat. No.98CH36178), 1998
Summary form only given. Optical glasses show higher information density recording compared with ... more Summary form only given. Optical glasses show higher information density recording compared with the usual photomaterials. Different linear and nonlinear phenomena were used for this goal. We study a new mechanism of glass excitation leading to modification of glass optical parameters that can be used for data recording
Conference Proceedings. LEOS'98. 11th Annual Meeting. IEEE Lasers and Electro-Optics Society 1998 Annual Meeting (Cat. No.98CH36243)
We present Laue diffraction experiments using a fs laser plasma X-ray ultrashort pulse source as ... more We present Laue diffraction experiments using a fs laser plasma X-ray ultrashort pulse source as preliminary experiments for time resolved X-ray Laue diffraction. The Laue method in X-ray diffraction experiments employs an X-ray beam consisting of a range of wavelengths to illuminate a stationary crystal.
The availability of ultrashort (100 fs) high intensity lasers capable of producing focused intens... more The availability of ultrashort (100 fs) high intensity lasers capable of producing focused intensities in excess of 10{sup 18} W/cm{sup 2} provides many new opportunities in studying the interaction of radiation with matter. The authors describe a new laser plasma facility constructed around a Cr: LISAF laser system currently capable of output energies of {approximately}1J in times of {approximately}100 fs. This facility will be directed initially towards basic studies of the interaction of intense ultrashort laser pulses with dense plasmas, and the generation and application of intense hard x-ray point sources. The laser system the authors have developed for this facility, uses the new solid-state laser material, Cr:LiSAF. This material has many advantages for the generation of intense ultrashort laser pulses. The spectral gain bandwidth is sufficiently broad for the amplification of pulses shorter than 100 fs in duration. Its fluorescence lifetime is long enough to permit the use of conventional flashlamp pumping, and its emission cross-section is such that it provides a small signal gains high enough to allow its use in a high powered chirped pulsed amplification laser architectures. Modifications currently being implemented onto their Cr:LiSAF laser system include improvements to pulse contrast, energy extraction, beam uniformity andmore » focusability. The system will soon be incorporated with a 52-port precision target chamber that will be equipped with a broad array of x-ray and plasma diagnostics. Several research programs are being designed around this facility. Two of these programs, those relating to the use of hard x-rays for the analysis of shock phenomena in solids and the general physics of extremely high magnetic fields will be presented.« less
With the intent of finding a sensitive photocathode material in the 130 Å (100eV) X-ray range for... more With the intent of finding a sensitive photocathode material in the 130 Å (100eV) X-ray range for use in a high resolution soft X-ray Conversion Microscope, photoelectron yields of several materials (mostly alkali halides), were measured at the National Institute of Standards and Technology's (NIST) Synchrotron Ultraviolet Radiation Facility II (SURF II). These measurements were made as a function of wavelength in the spectral range 115 Å-400 Å. The measured values are comparable to previous measurements of the photoelectron yields of these and similar materials, and to an existing model of photoemission [1–3]. We also determined the effects of prolonged exposure to X-ray light on performance. Moreover, because of the hygroscopic nature of Alkali Iodides, measurements of the photoelectron yield versus wavelength were repeated for samples of CsI that were kept in storage for periods of time to determine the effects of storage time and water absorption on the photoelectron yield.
ABSTRACT The NIST Extreme Ultraviolet (EUV) Reflectometry Facility was designed in the 1990s to a... more ABSTRACT The NIST Extreme Ultraviolet (EUV) Reflectometry Facility was designed in the 1990s to accommodate the largest multilayer optics envisioned at that time. However, with increasing power requirements for an EUV scanner, source collection optics have grown larger and more steeply curved than the original design would allow. To accommodate these changes, the mechanical and operational parameters of the facility have been upgraded. To access the entire surface of a larger optic, an auxiliary off-axis rotation stage has been installed allowing an increase in maximum optic size from 350 mm to 450 mm. Likewise, to deal with the deeper sags and steeper slopes of these optics, we have had to significantly expand our data analysis capabilities. In order to make these measurements, the incident radiation is reflected out of the vertical plane, allowing for measurements of effectively unpolarized radiation, an advantage for EUV lithography optics such as source collectors.
ABSTRACT Currently we are commissioning a second multilayer-based beamline to study the radiation... more ABSTRACT Currently we are commissioning a second multilayer-based beamline to study the radiation hardness of multilayers under extreme-ultraviolet (EUV) irradiation in an oxidizing atmosphere. Multilayer lifetime is one of the most important issues for the commercialization of extreme-ultraviolet lithography. The beamline employs a spherical multilayer mirror and a beryllium filter. The mirror demagnifies the source and reflects 13.4 nm radiation as well as visible light. The beryllium filter suppresses the visible light reflected by the mirror and provides also a barrier between the extremely clean storage ring vacuum and the water atmosphere of the test chamber.
Journal of research of the National Institute of Standards and Technology, 2003
The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons f... more The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This region includes the M3, M4, and M5 absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well. Separately, the effects of dynamic screening were observed as shown by an atomic calculation within the relativistic time-dependent local-density approximation. Dynamic screening effects influence the spectra at the 25 % level and are observed for both tungsten and tantalum. We applied these results to characterize spatially-resolved spectra of a tungsten integrated circuit interconnect obtained using a scanning transmission x-ray microscope. The results indicate tungsten fiducial markers were deposited into silica trenches with a depths of 50 % and 60 % of the markers' heights.
The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most a... more The absolute cryogenic radiometer (ACR), an electrical-substitution-based detector, is the most accurate method for measurement of radiant power in the extreme ultraviolet. At the National Institute of Standards and Technology, ACR-based measurements are currently used as standards from the infrared and into the vacuum ultraviolet, however, no radiometric facilities are currently in operation with enough incident power to use an ACR in the extreme-ultraviolet region. Therefore, we have installed transfer optics on an existing beamline to allow the installation of the ACR as an additional endstation. We will describe the current radiometric beamline, the ACR, and the high-throughput beamline, and the transfer-optical system. Finally, we will present the performance of the transfer optics and measurements of the beam profile and incident power of the new endstation.
ABSTRACT In this work, we discuss several parameters influencing extreme ultraviolet (EUV) resist... more ABSTRACT In this work, we discuss several parameters influencing extreme ultraviolet (EUV) resist qualification test results. The witness sample resist qualifications test is implemented on several different instruments world wide. The original protocol for the test developed by the tool manufacturer requires that a 300 mm wafer be exposed to a dose to clear in one hour. Also required is that the carbon contamination rate on the witness sample be mass limited, i.e., that the rate be saturated with respect to the EUV or e-beam intensity. Simple arguments have been presented in the past to show that the thickness of the carbon growth should be inversely proportional to the pumping speed and proportional to the area exposed if dose and duration were held constant. The present experiments demonstrate the real-life limitations of these arguments and provide validation to our area scaling procedure to equate test results done with 200 mm wafers to results expected for 300 mm wafers. In the process of studying the dependence of carbon growth on pumping speed, we encountered the important effect of increased partial pressure on the degree of intensity saturation.
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Papers by S. Grantham