摘要:

A two‐frame flash x‐radiography (FXR) system has been developed for studying the implosion hydrodynamics of particle beam driven, inertial confinement fusion (ICF) targets. This system consists of two micropoint flash x‐ray sources, two gated x‐ray cameras, and a mechanical framework for aligning these components with respect to the target. The tungsten micropoint sources yield a bremsstrahlung spectrum with an end‐point energy of 600 keV, an x‐ray dose of 8 mrad at 61 cm, a spot size of ∼100 &mgr;m, and an exposure time of ∼3 ns. A geometric magnification of 4× was employed in this radiographic arrangement, with an overall system resolving power of 4 line pairs/mm. This system has been used successfully to observe relativistic electron beam (REB) driven, ablative pusher target implosions.

ISSN:0034-6748    

DOI:10.1063/1.1137450

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

An infrared calorimeter system for measuring energy flux in a noisy electromagnetic environment has been developed. A thin (13 &mgr;) oxidized stainless‐steel foil is heated by energy flux and its temperature is determined by measuring the infrared emission from the back surface of the foil. The radiation is transported to the detector, which is located inside a double‐shielded enclosure, through a nylon‐tube infrared telescope. The calculated response time is 12 &mgr;s, and the measured peak‐to‐peak noise is equivalent to 0.4 mJ/cm2deposited energy.

ISSN:0034-6748    

DOI:10.1063/1.1137451

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The characteristics of a multicusp source that can produce a H2+or D2+ion fraction greater than 80% is described.

ISSN:0034-6748    

DOI:10.1063/1.1137452

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A new ion implanter has been designed for high‐dose predeposition in a semiconductor production line. It incorporates a microwave ion source, a 90° magnetic mass separator, and a rotating disk target chamber. Mass peak variations of PH3gas are shown as a function of the incident microwave power. The ion energy level can be varied from 10 to 50 keV. It makes 10 mA P+implantation (maximum 15 mA) possible. After beam adjustment, implantation is automatically carried out with a microcomputer. The operation rate of the implanter is remarkably improved due to the long lifetime of the modified microwave ion source and the low gas consumption. The dose nonuniformity of a 3‐in. wafer implanted with this implanter has a standard deviation (&sgr;) of 0.5%. This small nonuniformity results in a small &sgr; in the transistor current gain (less than 3.5%).

ISSN:0034-6748    

DOI:10.1063/1.1137453

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A modified hot‐wall epitaxy (HWE) system for the growth of multiple heterolayers is described which consists of two identical HWE furnaces. The substrate furnaces are mounted on a rotatable plate which allows the growth of heterolayers under nearly identical conditions for each individual layer. Single layers and multilayer heterostructures of the PbTe/Pb1−xSnxTe system were grown with this apparatus and typical results are presented.

ISSN:0034-6748    

DOI:10.1063/1.1137454

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A photoresist‐film thickness measurement method based on absorbance measurement is described. In this case, a 1‐&mgr;m‐thick photoresist film is coated on transparent glass, e.g., a Color Picture Tube panel having a 10–12‐mm thickness and a spherical, rough surface. To measure the absorbance, which corresponds to photoresist‐film thickness, the developed method employs a two‐dimensional scan of a 2‐mm‐diam light beam spot having two wavelengths, 365 nm (measuring wavelength) and 546 nm (reference). By switching wavelengths alternately at 25 Hz, total absorbance of the photoresist film and glass is measured with a ‘‘Dynode feedback’’ circuit system, but only the film thickness is displayed through simple signal processing. As experimental results, a minimum detectable thickness change of 0.001 &mgr;m (resolution) was obtained. The only remaining thing to be considered for practical use is a zero‐level discrepancy, due to different panel lots, for which the value was approximately equal to a 0.1‐&mgr;m thickness change.

ISSN:0034-6748    

DOI:10.1063/1.1137455

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A modulation scheme for electron–electron double resonance (ELDOR) spectrometers is presented. With this scheme an optimum stabilization signal for locking the pump microwave generator to the pumped electron paramagnetic resonance (EPR) line is generated. A separate pump power level and a separate magnetic field modulation amplitude are used for the purpose of locking. In general, such a modulation scheme introduces false ELDOR lines. These false lines disturb the real ELDOR signals, or introduce an ELDOR signal in the absence of any communication between the observed EPR line and the pumped EPR line. With the described modulation scheme the frequencies of the false ELDOR signals are limited to even multiples of the frequency of the wanted ELDOR signals. This makes a suppression of the false ELDOR lines easy.

ISSN:0034-6748    

DOI:10.1063/1.1137456

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

An analog electron tunneling spectrometer, based on a second harmonic detection technique, was digitalized with the aid of a small microcomputer. The method and the apparatus as well as some results obtained have been described in this report.

ISSN:0034-6748    

DOI:10.1063/1.1137457

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The problem of monochromator–microcomputer interfacing is discussed. As an example, a 0.5M Ebert monochromator is coupled to a PET microcomputer to provide photon counting (15‐MHz max), wavelength readout (0.004‐nm resolution), and scan control. Detailed circuit diagrams and supporting software are presented. Suggestions for adaptation to other monochromator–computer combinations are given.

ISSN:0034-6748    

DOI:10.1063/1.1137458

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A digital multiscaling module has been constructed to record time differentially in a series of single events with a time increment of 2 ns. The memory of the module consists of 1920 sequential bits which are read by a minicomputer via a CAMAC device for further data processing. The module was tested by a quantum beat experiment on the 6s6p3P1state of Hg.

ISSN:0034-6748    

DOI:10.1063/1.1137449

出版商:AIP    

年代:1983

数据来源: AIP