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The Helios compact synchrotron installed at IBM's Advanced Lithography Facility provides a unique opportunity to obtain compact synchrotron reliability data in an industrial environment. This paper presents data from the first eight months of user oriented operation of the machine. Running and uptime statistics are tabulated, as well as achieved performance parameters. Unscheduled downtime in the various subsystems is described.

Helios is an advanced superconducting storage ring designed for production of intense X-rays from synchrotron light, for X-ray lithography. It has recently being undergoing successful commissioning trials at Oxford prior to shipment, results of these trials and measurement of beam output properties are presented.

Investigations into the use of sulfur hexafluoride, SF6, as a gas-phase, infrared photochemical sensitizer have revealed several interesting phenomena. The expedient use of SF6 can produce an optimal quantity of nitrated product in the gas-phase, laser-induced nitration of cyclopen-tane. The optimal utilization of sulfur hexafluoride required critical optimization of both frequency and quantity. The results are described herein.

The sections in this article are 1 Superconducting Cyclotrons 2 Applications and Characteristics of Synchrotron Radiation 3 Technical description of a Compact Synchrotron

Synchrotron radiation from electron storage rings has the unique capacity to provide the several kilowatts of continuous X-ray power necessary for production scale X-ray lithography-. While national laboratories have developed electron storage ring technology to an exact science and can provide X-ray beams of an intensity and quality appropriate for lithography, they have not built machines optimized for lithography and designed to be replicated in semiconductor fabrication facilities. Since 1983, Oxford Instruments have been working on the development of a practical synchrotron X-ray source, called Helios. Final system tests will commence this spring on the initial Helios compact synchrotron.

During 1991 the Oxford Instruments’ compact synchrotron x‐ray source Helios was installed at IBM’s Advanced Lithography Facility, following factory tests in Oxford during 1990. The machine has met or exceeded all performance specifications at the East Fishkill site. Since January, 1992 it has been run routinely for lithography development work. Running and reliability statistics are being generated, and the results for the first five months are presented here.

Helios is a compact superconducting Synchrotron X-ray source designed specifically for lithography. It will produce a total X-ray power of 8.2 kW when the design stored beam of 200 mA is achieved. The first phase of commissioning has just been completed in less than 2 months. A stored beam of 305 mA has been accumulated at the injection energy of 200 MeV and 55 mA has been accelerated to the full energy of 700 MeV.

We have studied $\ensuremath{\omega}$ photoproduction using 7.5- to 10.5-GeV tagged photons. Cross sections from hydrogen lie 22% below the bubble chamber results of Ballam et al., but have a similar slope. Density matrices indicate approximate $s$-channel helicity conservation. The proton-neutron cross-section difference is midway between zero and the value suggested by the $\ensuremath{\gamma}p\ensuremath{-}\ensuremath{\gamma}n$ total-cross-section difference. Fits to the cross sections for D, Be, and Cu and those for Be, C, Al, Cu, and Pb from a previous experiment yield ${\ensuremath{\sigma}}_{\ensuremath{\omega}N}=25.4\ifmmode\pm\else\textpm\fi{}2.7$ mb and $\frac{{{\ensuremath{\gamma}}_{\ensuremath{\omega}}}^{2}}{4\ensuremath{\pi}}=7.6\ifmmode\pm\else\textpm\fi{}1.2$.

eta..gamma.. decays of rho/sup 0/, ..omega.., and phi are studied. We find GAMMA (phi..-->..eta..gamma..) =55 +- 12 keV. Our data admit two solutions for (rho/sup 0/, ..omega..) ..-->..eta..gamma..: Either GAMMA (rho/sup 0/..-->..eta..gamma..) =50 +- 13 keV, GAMMA (..omega -->..eta..gamma..) =3.0/sup +2//sup .//sup 5//sub -//sub 1//sub .//sub 8/ keV, and the (..omega..,rho) ..-->..eta..gamma.. relative decay phase is near zero; or GAMMA (rho/sup 0/..-->..eta..gamma..) =76 +- 15 keV, GAMMA (..omega -->..eta..gamma..) =29 +- 7 keV, and the decay phase is near 180degree. (AIP)

Inclusive $\ensuremath{\eta}$ photoproduction has been studied at 9.7 GeV, on hydrogen and deuterium targets. A simple, parameter-free ${\ensuremath{\rho}}^{0}$-dominance model adequately fits the forward cross sections, but overestimates the cross section at large momentum transfer.

We report measurements of inelastic photoproduction of ..omega.. and rho/sup + -/mesons from hydrogen and deuterium at incident photon energies in the range 7.5-10.5 GeV. For ..omega delta.. and rho/sup -/..delta../sup + +/ production differential cross sections dsigma/dt' and spin density matrices are presented. For higher missing masses the cross sections dsigma/dM/sub X//sup 2/ and invariant structure functions F(x) are also given. The data are compared to a one-pion-exchange model. We conclude that pion exchange is dominant for inelastic ..omega.. photoproduction, but unimportant for rho/sup + -/during annealing, even though the resistively determined transport scattering time increased by a factor of 7.8 during annealing. Orbital depairing was found to follow a relation zeta = zeta/sub 0/ + ..cap alpha..H/sup 2/ and to increase with annealing in a manner expected from the change in mean free path determined from measurements of H/sub cnu/.

This investigation of multiphase flow, supported jointly by the Texas Petroleum Research Committee, The University of Texas, and many companies affiliated with the oil industry, is an effort to develop a reliable method of predicting static pressure loss during two-phase horizontal flow in 2-in. pipe. The 165 two-phase tests were run in 1688 ft of 2-in. steel line pipe with water, distillate, and crude oil in connection with natural gas. The liquid flow rate ranged from 50 to 2500 B/D, with gas rates up to 6 MMscf/D. The range of mean line pressures was from 70 to 850 psig. Pressures were measured at 12 line locations, the liquid holdup was measured at two locations, and flow patterns were photographed through plastic pipe sections. From the data, correlations have been developed for liquid holdup and for an energy loss factor. The correlations can be used in conjunction with a derived equation to predict two-phase horizontal pressure losses. The prediction method is carefully outlined and, although it lends itself to computer usage, it is relatively fast and just as accurate by hand. Applied to the original data, the method yielded pressure gradients with an average error of 2.3 percent.

Critical opalescence of a binary liquid mixture, normal perfluoroheptane and iso‐octane has been investigated by light and small‐angle x‐ray scattering over a broad range of s/λ, where s=2 sin (θ/2), λ is the wavelength in the medium, and θ is the scattering angle. The scattering data show that the critical opalescence observed in this system is essentially the same as has been found in other binary liquid mixtures.

We have determined the branching ratio for ϱ ° → ηγ to be less than 0.1% at the 90% confidence level.

The Oxford Instruments group is constructing a novel compact electron storage ring intended for use as a powerful source of soft X‐rays. The main application foreseen for such a source is in X‐ray lithography for future sub‐micron semiconductor geometries, but other research applications are also anticipated.At the heart of the source are two 180° superconducting dipole magnets which reduce the bending radius from the several meters common in conventional VUV rings to just over 0.5 meters. Consequently the overall dimensions of the storage ring itself are extremely compact, lending the device to industrial applications.Injection into the ring will be by linear accelerator at energies up to 200 MeV via a suitable beam transport arrangement of focusing and bending magnets with simultaneous pulsed operation of septum and kicker magnets in the ring itself. The latter is corrected for chromaticity effects.The vacuum system will be of UHV standard throughout, with pumping provided by the superconducting dipoles...

Over a period of years, this laboratory has accumulated an array of cells used in laser-induced, gas-phase irradiations. We attempt to keep pace with new cells that might be useful in the area of laser-induced chemistry. As different cells are tried, some are not useful, for one reason or another. A common problem encountered with some of these cells is that they will not meet the high vacuum standards necessary for the Army's research.

Successful results on a development scale have demonstrated the benefits of x‐ray lithography for producing fine features with broad process latitude. This paper is concerned with design of an x‐ray source appropriate for production scale utilization of this technology. General considerations of throughput required show that, regardless of type, the source must provide several kilowatts of continuous x‐ray power. At present, only synchrotrons can achieve this level. Conventional synchrotrons are too large for installation in a wafer fabrication facility, but superconducting synchrotrons can be relatively compact. Oxford Instruments Ltd. are presently building high‐energy lithography illumination by Oxford’s synchrotron (HELIOS), a compact superconducting synchrotron, for installation in the IBM Advanced Lithography Facility at East Fishkill, New York. HELIOS will produce over 8 kW of continuous x‐ray power with a characteristic critical wavelength of 0.84 nm. The design and performance of HELIOS are described, together with a discussion of the design choices which lead to the key features of HELIOS.