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Effective and rigorous technical peer reviews provide quality to a product realization process. This paper proposes a five-step peer review process based on survey of the literature, experience with peer reviews, and pilot trials. Feedback was collected and integrated as lessons learned, resulting in a process that addresses key attributes of a peer review: roles & responsibilities; requirements; rigor; peer identification, independence, and external engagement; and follow-up actions. An idea for a tool is provided to assist with rigor level determination and scoping of the peer review. Use of this peer review process can yield consistent peer review practices surrounding peer review practices for product realization teams.

The EUV Engineering Test Stand (ETS) has demonstrated the printing of static and scanned 100nm dense features. This milestone was first achieved in 2001 with a developmental set of projection optics (P0 Box 1) and with a low power LPP source (40W drive laser). Since that time, the source has been upgraded to a 1500W (3 chains, 500W per chain) TRW drive laser. Operating with one chain (500W), the printed static images for 100nm features are comparable to those obtained with the low power source, while exposure time was decreased by a factor of 15 to 30. One hundred nanometer dense features printed in step-and-scan mode are of the same image quality as those obtained in static imaging. The stages have demonstrated combined x any y j fitter values of 2 to 4nm RMS over most of the wafer stage travel range, at the designed scanned speed of 10mm/s at the wafer. This value is less than half of the designed value and provides sufficient stability to support printing of 70nm features. EUV specific sensors at the wafer and reticle planes have been demonstrated with the TRW laser and integration will be completed later this year. The developmental projection optics (P0 Box 1) will be replaced later this year with an improved projection optics system (PO Box 2) capable of printing 70nm dense features.

This report compared data taken on the Modular Bremsstrahlung Simulator using copper jacketed (cujac) cables with calculations using the RHSD-RA Cable SGEMP analysis tool. The tool relies on CEPXS/ONBFP to perform radiation transport in a series of 1D slices through the cable, and then uses a Green function technique to evaluate the expected current drive on the center conductor. The data were obtained in 2003 as part of a Cabana verification and validation experiment using 1-D geometries, but were not evaluated until now. The agreement between data and model is not adequate unless gaps between the dielectric and outer conductor (ground) are assumed, and these gaps are large compared with what is believed to be in the actual cable.

Static and scanned images of 100nm dense features for a developmental set of l/14 optics (projection optics box # 1, POB 1) in the Engineering Test Stand (ETS) were successfully obtained with various LPP source powers last year. The ETS with POB1 has been used to understand initial system performance and lithographic learning. Since then, numerous system upgrades have been made to improve ETS lithographic performance to meet or exceed the original design objectives. The most important upgrade is the replacement of POB 1 with an improved projection optics system, POB2, having lower figure error (l/20 rms wavefront error) and lower flare. Both projection optics boxes are a four-mirror design with a 0.1 numerical aperture. Scanned 70-nm dense features have been successfully printed using POB2. Aerial image contrast measurements have been made using the resist clearing method. The results are in good agreement to previous POB2 aerial image contrast measurements at the subfield exposure station (SES) at Lawrence Berkeley National Laboratory. For small features the results deviate from the modeling predictions due to the inherent resolution limit of the resist. The intrinsic flare of POB2 was also characterized. The experimental results were in excellent agreement with modeling predictions. As predicted, the flare in POB2 is less than 20% for 2μm features, which is two times lower than the flare in POB1. EUV flare is much easier to compensate for than its DUV counterpart due to its greater degree of uniformity and predictability. The lithographic learning obtained from the ETS will be used in the development of EUV High Volume Manufacturing tools. This paper describes the ETS tool ETS tool setup, both static and scanned, that was required after the installation of POB2. The paper will also describe the lithographic characterization of POB2 in the ETS and cmpare those results to the lithographic results obtained last year with POB1.

Full-field imaging with a developmental projection optic box (POB 1) was successfully demonstrated in the alpha tool Engineering Test Stand (ETS) last year. Since then, numerous improvements, including laser power for the laser-produced plasma (LPP) source, stages, sensors, and control system have been made. The LPP has been upgraded from the 40 W LPP cluster jet source used for initial demonstration of full-field imaging to a high-power (1500 W) LPP source with a liquid Xe spray jet. Scanned lithography at various laser drive powers of >500 W has been demonstrated with virtually identical lithographic performance.

The Engineering Test Stand (ETS) is an 'alpha-class' Extreme Ultraviolet (EUV) lithography tool designed to demonstrate full-field EUV imaging and provide data required to accelerate production-tool development. The illumination system of the ETS is based on a laser-produced plasma (LPP) source using a recirculating Xe target medium. A Nd:YAG laser focused onto a Xe-gas or liquid target creates a plasma producing 13.4 nm radiation, at the center of the Si/Mo multilayer mirror passband. A condenser system, comprised of multilayer-coated and grazing incidence mirrors, collects the EUV radiation and directs it onto a reflecting reticle. A 1500 W LPP source has been integrated with the ETS and used for lithography. Two Xe spray sources have been evaluated, a cluster jet and a liquid spray jet. The cluster jet Xe source output rapidly degraded from heating of the hardware by the plasma causing the Xe clusters to be too small for efficient conversion. The TRW-designed liquid spray jet operates stably for hours and with tripled conversion efficiency into the condenser optics, producing EUV in the ETS.

The EUV Engineering Test Stand (ETS) has demonstrated the printing of 100-nm-resolution scanned images. This milestone was first achieved while the ETS operated in an initial configuration using a low power laser and a developmental projection system, PO Box 1. The drive laser has ben upgraded to a single chain of the three-chain Nd:YAG laser developed by TRW. The result in exposure time is approximately 4 seconds for static exposures. One hundred nanometer dense features have been printed in step-and-scan operation with the same image quality obtained in static printing. These experiments are the first steps toward achieving operation using all three laser chains for a total drive laser power of 1500 watts. In a second major upgrade the developmental wafer stage platen, used to demonstrate initial full-field imaging, has been replaced with the final low-expansion platen made of Zerodur. Additional improvements in the hardware and control software have demonstrated combined x and jitter from 2 to 4 nm RMS Over most of the wafer stage travel range, while scanning at the design scan speed of 10 mm/s at the wafer. This value, less than half of the originally specified jitter, provides sufficient stability to support printing of 70 nm features as planned, when the upgraded projection system is installed. The third major upgrade will replace PO Box 1 with an improved projection system, PO Box 2, having lower figure error and lower flare. In addition to these upgrades, dose sensors at the reticle and wafer planes and an EUV- sensitive aerial image monitor have been integrated into the ETS. This paper reports on ETS system upgrades and the impact on system performance.

The Engineering Test Stand (ETS) is an EUV lithography tool designed to demonstrate full-field EUV imaging and provide data required to accelerate production-tool development. Early lithographic results and progress on continuing functional upgrades are presented and discussed. In the ETS a source of 13.4 nm radiation is provided by a laser plasma source in which a Nd:YAG laser beam is focused onto a xenon- cluster target. A condenser system, comprised of multilayer-coated and grazing incidence mirrors, collects the EUV radiation and directs it onto a reflecting reticle. The resulting EUV illumination at the reticle and pupil has been measured and meets requirements for acquisition of first images. Tool setup experiments have been completed using a developmental projection system with (lambda) /14 wavefront error (WFE), while the assembly and alignment of the final projection system with (lambda) /24 WFE progresses in parallel. These experiments included identification of best focus at the central field point and characterization of imaging performance in static imaging mode. A small amount of astigmatism was observed and corrected in situ, as is routinely done in advanced optical lithographic tools. Pitch and roll corrections were made to achieve focus throughout the arc-shaped field of view. Scan parameters were identified by printing dense features with varying amounts of magnification and skew correction. Through-focus scanned imaging results, showing 100 nm isolated and dense features, will be presented. Phase 2 implementation goals for the ETS will also be discussed.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

PURPOSE The camptothecin derivative irinotecan has demonstrated clinical activity in metastatic colorectal carcinoma in both chemotherapy-naive and fluorouracil-refractory patients. 9-Aminocamptothecin (9-AC; NSC 603071), another camptothecin derivative, was selected for clinical development based on preclinical activity, including cures in human tumor xenografts resistant to standard anticancer agents. We report a phase II trial of 9-AC in patients with previously untreated metastatic colorectal carcinoma. PATIENTS AND METHODS Colorectal cancer patients with measurable disease, a performance status of 0 to 2 (Zubrod), and no prior chemotherapy for metastatic disease received 9-AC. A cycle of therapy was 35 microg/m2/h for 72 consecutive hours (840 microg/m2/d for 3 days) and rest on days 4 to 14; a course of therapy was defined as two cycles (28 days). Patients were assessed for response after two courses. RESULTS Seventeen patients with metastatic colorectal cancer were entered onto this trial. No complete or partial responses were noted. Treatment was well tolerated; toxic effects consisted mainly of neutropenia, nausea, vomiting, stomatitis, fatigue, and anemia. Grade 3 to 4 toxicity was limited to neutropenia (grade 3 in four patients and grade 4 in six), anemia (grade 3 in two patients), and vomiting (grade 3 in two patients). No grade 3 or 4 diarrhea occurred. Only two patients had their 9-AC dose reduced to 30 microg/m2/h. The median nadir absolute granulocyte count (AGC) was 1,500/microL. The median number of courses given was two and the median time to disease progression was 8 weeks. CONCLUSION At the dose and schedule used in this trial, 9-AC lacked antitumor activity in metastatic colorectal cancer. 9-AC infusion schedules of longer duration are currently being investigated in this disease.

A comprehensive approach to developing intense pulse microwave diagnostics for measuring the performance of a high‐power microwave source is presented. Both conventional and new diagnostic techniques were used. Hence all measurements were made in a redundant fashion allowing small error bars in the measured data. The output power was diagnosed using four methods: two transmitting–receiving systems, two circular waveguide directional couplers, calorimetry, and gaseous breakdown. The operating frequency was measured using three methods: bandpass filters, a heterodyne receiver, and a homodyne receiver. The diagnostics were evaluated by using a 12‐vane S‐band inverted relativistic magnetron operating at 1 MV, 0.31 T, and 5 kA which reliably produced 3.15‐GHz microwaves at powers of approximately 100 MW for pulse lengths variable from 5 to 70 ns. The microwave power pulse had a rise time of approximately 2 ns.

Relativistic scaling laws ore presented to aid in the analysis and design of relativistic (high voltage) magnetrons. The voltage and magnetic field laws are rigorously derived at the intersection of the Hull cutoff and Buneman-Hartree oscillation threshold. The behaviour of relativistic space charge limited flow in the absence of a magnetic field leads to a plausible scaling law for the current. A simple estimate of the efficiency demonstrates the penalty involved in operating at relativistic voltages. The synchronous electron rotation velocity is shown to determine the magnitude of relativistic effects. Finally, the difficulty of simultaneously satisfying the relativistic and the non-relativistic design rules is shown.

Reported in this paper are the results of an experiment to produce high‐power Ku‐band (12–18 GHz) microwave radiation from a backward wave oscillator (BWO) driven by a relativistic electron beam. Experimentally measured output power was about 250 MW at 12.5 GHz and 100 MW at 14 GHz. A description of the slow wave structure is given along with theoretical predictions of the vacuum waveguide dispersion relations. The diagnostics to determine the frequency and power of the device are described. Finally, comparisons between the experimentally measured frequency and power, and the analytic and numerical simulations of the BWO are made.

An electro‐optical technique has been developed to measure high‐frequency electric fields in free space. Electrically induced birefringence in an electro‐optical crystal is used to modulate a linearly polarized continuous‐wave laser beam. The modulation impressed on the laser beam contains both frequency and field intensity information. A way to use this technique as both a frequency and power meter is discussed. A proof‐of‐principle experiment has been carried out with a 3.1‐GHz magnetron source.

This work compares a carefully designed experiment to measure photoemission with the predictions of three different codes (CEPXS/ONETRAN, TIGERP, and TIGER) for the complex bremsstrahlung spectra typical of very intense pulsed power x-ray generators. The Monte Carlo codes TIGER and TIGERP can calculate the net photon-induced electron emission but accurate results may require that statistical error be minimized. CEPXS/ONETRAN is a new deterministic coupled electron/photon transport code that is faster than Monte Carlo and is not subject to statistical error. The comparison of net yields is a sensitive test of the relative accuracy and efficiency of these various codes. We find that all of the codes substantially agree with the experiments for the forward net yields. However, for reverse net yields from high-Z materials, the codes overpredict relative to measurements.

A method for measuring the peak power of a single microwave pulse in an oversized circular waveguide is presented. This measurement technique uses a new circular waveguide calorimeter to measure the total energy of the microwave pulse. The peak power is determined from the total energy and by measuring the pulse shape with a fast diode detector connected to a circular waveguide directional coupler. Measurements have been made at 3.15 GHz for power levels up to 200 MW. Pulse widths were varied between 5 and 50 ns giving pulse energies between 1 and 10 J.

Switching effects in thin-film sandwiches of tetrabutyltin polymerized by electron bombardment are described. The switch was a memory type with two distinct metastable resistance states. The conduction mechanism may have been either Schottky emission or the Poole-Frenkel effect, and the switching can be explained by phase changes caused by ohmic heating along filamentary paths. A forming process was not necessary since the virgin junctions were already in the low-resistance state. The switching time was of the order of one microsecond and the junctions could be switched at least one hundred times.

Three new types of directional couplers are described for use in overmoded circular waveguide operating in the TM0 1 mode. The types are (1) circular/rectangular waveguide multihole couplers, (2) circular waveguide/coaxial multihole couplers, and (3) circular waveguide loop couplers. These directional couplers are designed to diagnose intense pulsed microwave systems in the frequency range 3 - 18 GHz. Coupling coefficients vary between 50 dB and 70 dB with directivities between 13 dB and 20 dB. These devices have been used to measure the output powers of relativistic magnetrons and backward wave oscillators (BWOs) in the power range 100 MW to 300 MW.

A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

Plasma impedance measurements have been made in the frequency range around the lower hybrid frequency, by plotting the complex reflection coefficient as the frequency was varied. As demonstrated by comparison with the calculated values of the lower hybrid frequency, this inherently non-perturbing technique is a sensitive indication of the occurrence of lower hybrid resonance in the plasma.

A new calorimeter for single intense microwave pulses has been designed and tested. The device was constructed in WR284 rectangular waveguide and was operated at frequencies from 2.5 to 4.3 GHz with a tunable instantaneous bandwidth of approximately 500 MHz. The calorimeter used a single thermistor to measure the energy deposited on a carbon absorber having a microwave power absorbance of 90%. The calorimeter was tested at power levels from 100 to 1000 MW for pulse lengths of 12–6 ns, respectively. The sensitivity of the device was 200–300 mV/J.

Twenty-five patients with previously untreated adenocarcinoma of the ovary (International Federation of Gynecology and Obstetrics, stages II, III, and IV) were placed on a six-drug trial (CHAMP-5) for 18 months. This trial consisted of 28-day cycles of hexamethylmelamine, doxorubicin, and cisplatin alternating with hexamethylmelamine, cyclophosphamide, methotrexate, and 5-FU. After a minimum follow-up of 31 months, 14 (56%) of the 25 evaluable patients achieved complete or partial response and nine (36%) achieved complete pathologic response. Although CHAMP-5 is effective in the treatment of ovarian cancer, the results in these patients are not substantially different from those achieved with hexamethylmelamine, doxorubicin, and cisplatin alone.