Fast, Microprocessor Driven, Data Acquisition for Fermilab Experiment E-705

Data rate in excess of 105 16-bit CAMAC words/sec, with peak rates of up to 2×106 words/sec, are expected from Fermilab experiment E-705. To handle such rate, a fast Data Acquisition System was designed, composed of several CAMAC Smart Controllers, sending their data, in a combined serial/parallel organization, to a VME based data collection and forwarding system. Such a system, contained in a VME Crate, consists of homebuilt data receiver and transmitter boards, a Motorola VME110, 68000 based, Single Board Computer acting as a supervisor, and a large (?4 Mbytes) buffer memory. Data filtering capabilities will be added to the system with the inclusion of several MK 75602 Single Board Computers, acting as processing cells.     

Radiation-Insensitive Silicon Oxynitride Films for Use in Silicon Devices---Part II

We report here on the interface state densities at the Si/Silicon Oxynitride (SiON) interface before and after ionizing irradiation, on extended B T tests on Si/SiON capacitors, and on the fabrication and properties of SiON passivated bipolar transistors and P-channel IGFETs. Preliminary data are also presented for gold and copper diffused capacitor structures. The fast state density Nfs after a 1/2 hr. anneal in H2 at 900°C is approximately 8x1010 eV-1 cm-2 near midgap, and increases into the high 1011 eV-1 cm-2 range near the band edges. After an absorbed dose of 1.3 Mrads, the densities near midgap had increased by a factor of 1.3, but showed little change near the band edges. B-T tests under negative bias at l.6×106 V/cm and at temperatures up to 330°C showed a Vfb drift of 2-3 V to more positive values during the first hour, which did not change thereafter; very little drift occurred under positive bias and the same test condition. Test duration was 63 hours for either polarity of bias. This BT-stability, observed on Si/SiON/Al structures, is often lost after gold wire thermocompression bonding. Si/SiON/ tungsten-gold contacts showed no deterioration after thermocompression bonding. SiON passivated type 16F NPN bipolar transistors had initial gain characteristics similar to SiO2 passivated controls, whereas their tolerance to ionizing radiation was much greater. Degradation of hFE to 50% of the initial gain occurred for the SiO2 passivated devices after an absorbed dose of about 1 Mrad and for the SiON passivated devices after 35 Mrads.     

A Proportional Wire Chamber Electronics System Utilizing CAMAC

This report describes a system of electronics to be used with a proportional wire chamber hodoscope. The system, which uses CAMAC packaging and data handling philosophy, consists of octo (8 channel) wire signal amplifiers, octo 4-bit per wire latch modules, gate fanout modules, crate controllers, and two types of data processor-interface units to the SDS 9300 computer. System operation is explained, and each component is described.     

MIDAS: A Multilevel Interactive Data Acquisition System

A system is described for using a medium scale computer in real time data acquisition, analysis, and control of high-energy physics experiments utilizing wire spark chambers.     

The Princeton Cyclotron Data Acquisition System

The Princeton Cyclotron minicomputer based data acquisition system is used for nuclear physics research. The system includes eight 13-bit resolution ADC's, computer readable scalers and a general analog and digital I/O crate interfaced to a Data General Eclipse S/230 with 80K words of memory running under the RDOS operating system. The acquisition program ACQUIRE is a general multiparameter sorting and analysis code capable of high data rates (40 kHz without loss for a repetitious pulser).     

半导体器件与电路辐照响应测试系统

介绍用于测量ＭＯＳ电容、ＭＯＳＦＥＴ、半导体元器件和集成电路辐照效应的微机测试系统及其功能，并给出该系统在半导体辐射损伤研究甲的应用实例．     

A New Instrument Concept for Gamma Ray Astronomy

A new instrument concept that utilizes the principle of the Total Absorption Shower Cascade (TASC) detector is proposed for gamma ray astronomy in space. Using the TASC detector to measure the gamma ray energy and wire chamber arrays to measure the incident angle, an instrument package designed to measure gamma rays having energies greater than 100 MeV is being proposed for a large satellite such as NASA's proposed High Energy Astronomy Observatory. The proposed instrument has a minimal flux sensitivity of 2 × 10-10 photons/cm2 sr sec which will allow gamma rays with energies up to 104 GeV to be measured. An energy resolution (FWHM) for the TASC detector of ~l percent at 10 GeV has been measured and an angular resolution of ~1 degree appears to be obtainable for the wire chamber arrays.     

A TDC-Based System for X-Ray Imaging Detectors

An image acquisition system is presented for use with position sensitive detectors (PSD). The system is based on a high-resolution time-to-digital converter (TDC) and a field programmable gate array (FPGA). The detectors use gas as absorbing medium and two delay lines to identify the coordinates of each detected particle. The TDC translates the time information coming from the delay lines into digital words, from which the particle position coordinates are encoded. The FPGA is responsible for processing each event, controlling the data acquisition and communicating with a personal computer. 256 pixels$times$256 pixels images are stored into an on-board memory. This resolution is increased to 512 pixels$times$512 pixels by using a time multiplexing technique. The maximum data acquisition rate is 1.2 million events per second. X-ray images obtained with the system are shown, which illustrate the overall performance.     

Electron Injection Studies of Radiation Induced Positive Charge in MOS Devices

Avalanche injection and internal photo-emission techniques have been used to study the capture of electrons by positive charges introduced into the oxide layers of MOS capacitors. These two techniques have been used to study the positive charge in Al gate and poly-Si gate capacitors. The electron capture crosssection of this charge has been found to depend on the composition of the interface; positive charge at the Si interface tends to have a coulombic electron capture cross-section (~ 4×10-13cm2), while that at the alumninum interface has a non-coulombic electron capture crosssection (? 10-14cm2). The location of the positive charge induced by radiation under positive or negative bias has been determined in a completely non-destructive manner by photocurrent-voltage experiments. It has been found that under a positive irradiation bias, positive space charge accumulates within ~ 50 A of the Si-SiO2 interface, while under a negative bias, the space charge is within ~ 50 ? of the Al-SiO2 interface. In both cases there is evidence for some charge at the other interface introduced by the irradiation.     

多路穆斯堡尔谱数据获取与处理系统

本文叙述了一个以BC3-80微型计算机为基础,通过一个以Z80-CPU为中心的控制机与8个带有存贮器的数据获取通道组成的多路数据获取与处理系统。这个系统除能对8个通道的数据进行数据获取外,同时可以对其进行显示、保存和数据处理。它与穆斯堡尔谱仪部件相接,构成一个恒加速穆斯堡尔谱仪系统。 这个系统配上高计数率多丝正比室,可以使穆斯堡尔谱的探测效率大大提高。多丝室中的每根丝的信号分别通过各自的放大器、单道分析器,由相应的数据通道记录下来,然后由微机进行相加和处理。另一方面,这个系统还可以利用不同的通道同时测出样品的透射谱和散射谱,同时得到样品的内部和表面信息。     

Data acquisition workstation for Oak Ridge Electron LinearAccelerator

A multiparameter data acquisition system for the Oak Ridge Electron Linear Accelerator (ORELA) is described. This system uses a personal computer and a data handler with a 2048-word buffer. The buffer can accept data at a rate exceeding one million events per second in bursts of 512 words 64-b in length. The acquisition system, limited by software, can acquire data from one, two or three digitizers; multiplex up to four detectors; read and control up to 16 scalers or registers; and output up to 32 DC logic lines that can be used to control external instrumentation. Software was developed for the OS/2 operating system, supporting multiparameter data storage for up to those million channels. Data can be collected in background mode to make the computer available for other tasks while collecting data. The system supports multiparameter biasing and can collect, crunch, and store data at rates of 30000 events/s, each event containing up to 64 b of information     

Reduction and compensation of lattice stress in high energy P+ and P+Sb implanted silicon

1IntroductionIontwlantationisaYerywtortantVLSItechnology.High-energyionimPlanta-tionhasattractedmuchinterestasitmayplayanimportantroleincreatingdeepp-njunctions,buried1ayers,deepburiedconnectionsbetweendevices,p-well,andn-well,whichareassociatedwithVLSIcircultfabri.ati..[1~3].InordertoapplyMeVenergyionforlantationtechnologytodevicefabrication,thestructure,natureanddepthdis-tributionofdefectsinimplantedandannealedsillconshouldbecarefullyinvestigated.Moreover,itisalsonecessarytopaycloseatte…     

Neutron Damage Mechanisms in Charge Transfer Devices

A study of neutron damage mechanisms in charge transfer devices has been performed with emphasis placed on investigation of dark current increases. MOS capacitors were used to determine damage coefficients that are applicable to the radiation response of CCDs. Measurements of dark current density in CCDs were made following neutron bombardment. A unique value for generation-lifetime damage coefficient was determined (Kg = 7.0 × 106 n-sec/cm2) using MOS capacitors on both n- and p-type silicon substrates and this value was then used to calculate the expected change in dark current density with neutron fluence in a charge transfer device. The calculated value is in good agreement with the present experimental value of ~4×l0-11 nanoamps per neutron. A qualitative explanation is given to account for the nearly two-orders-of-magnitude difference between Kg and recombination-lifetime damage coefficients which is based in part on the nature of neutron damage in a depletion region. An explanation is also given to account for the more than six-orders-of-magnitude difference between Kg and storage-time damage coefficient. It is demonstrated that a moderate reduction in the operating temperature of a charge transfer device should result in substantial radiation tolerance in terms of neutron-induced increases in dark current.     

Imaging Properties of a Positron Tomograph with 280 Bgo Crystals

The basic imaging properties of the Donner 280-BGO-Crystal positron tomograph were measured and compared with the same system when it was equipped with 280 NaI(T1) crystals. The NaI(T1) crystals were 8 mm × 30 mm × 50 mm deep, sealed in 10 mm wide stainless steel cans. The BGO crystals are 9.5 mm wide × 32 mm × 32 mm deep and as they are not hygroscopic do not require sealed cans. With a shielding gap of 3 cm (section thickness 1.7 cm FWHM) the sensitivity of the BGO system is 55,000 events per sec for 1 ?Ci per cm3 in a 20 cm cylinder of water, which is 2.3 times higher than the NaI(T1) system. For a 200 ?Ci/cm line source on the ring axis in a 20 cm diameter water cylinder, the BGO system records 86% of the scatter fraction and 66% of the accidental fraction of the NaI(T1) system. The lower light yield and poorer time resolution of BGO requires a wider coincidence timing window than NaI(T1); however, the ability to use full-energy pulse height selection with a 2.3-fold improvement in sensitivity results in an overall reduction in the fraction of accidental events recorded. The in-plane resolution of the BGO system is 9-10 mm FWHM within the central 30 cm diameter field, and the radial elongation at the edge of the field in the NaI(T1) system has been nearly eliminated.     

微处理器中子单粒子效应测试系统设计与试验研究

为开展微处理器的空间大气中子单粒子效应研究,以一款TI公司65 nm CMOS工艺的微处理器为研究对象,研制了一套微处理器中子单粒子效应测试系统。该测试系统可实现对被测微处理器的单粒子翻转、单粒子功能中断和单粒子闩锁效应的实时监测。利用加速器中子源,对该微处理器开展14 MeV中子辐照试验。试验结果表明,中子注量累积达3?5×1011 cm-2时,该器件未发生单粒子锁定效应。但总线通信、模数转换等功能模块发生了多次单粒子功能中断,其中集成总线通信接口模块为最敏感单位,试验获得的器件中子单粒子效应截面为6?6×10-11 cm2。     

Integral Type Position-Sensitive Proportional Chamber with Multiplexer Readout System

A new position-sensitive detector with a multiplexer readout system for synchrotron radiation measurements is described. The detector consists of many proportional chamber cells with capacitors for charge accumulation. Charges delivered from a detector cell are accumulated in an associated capacitor during a measuring time. The accumulated charges are transferred to a charge-sensitive amplifier through a multiplexer channel which is addressed by binary coded signals. This process corresponds to the integral type radiation measurement which has no dead time in the pulse measurement. Each cell is regarded as a memory cell containing information about X-ray photons. Experiments carried out with a direct X-ray beam show that the detecting system is applicable to a wide range of photon rates from 103 cps to 108 cps per cell.     

Physical Mechanisms of Radiation Hardening of MOS Devices by Ion Implantation

This paper reports experimental and analytical studies performed on Al+ ion-implanted MOS capacitors. Electrons and holes were excited in SiO2 by a low-energy electron beam, the resultant current measured, and the results then compared to findings for unimplanted specimens. Comparisons were also made of flatband voltage shifts for implanted and unimplanted devices. Analytical expressions, based on a physical model, are developed which explain the experimental results. In this model, decreases in collected current and changes in flatband voltage shift are attributed to both hole and electron trapping in the implanted region. Thus, the model contains three critical parameters: the mobility-lifetime products for both holes and electrons in the implanted region and the depth of this region. While a range of these variables satisfy either the current vs voltage measurements or the flatband-voltage-shift results, considered jointly these experiments provide specific values for all three parameters. The depth of the implanted region so determined agrees well with experimental observation, and the mobility-lifetime products calculated for different experimental conditions are consistent. The product for holes (~3.5 × 10-13 cm2/V) is substantially smaller than that for electrons (~2 × 10-12 cm2/V), indicating that holes are more easily trapped in the implanted zone than electrons. The fact that more electrons than holes are actually trapped in the case of gamma irradiation under positive bias is explained by the model. Bias dependence is also explained, as well as the fact that there is an optimum implantation energy for minimizing flatband shifts.     

在线中子活化分析系统关键参数的蒙特卡罗模拟

针对在线瞬发γ中子活化分析（PGNAA）系统的要求,利用MCNP程序对不同慢化材料（重水、石蜡、聚乙烯等）厚度、铅屏蔽厚度、样品厚度及大小进行模拟计算分析。计算结果表明,以厚9cm的石蜡作慢化材料,厚2cm的铅作γ屏蔽层,厚7cm、半径10cm的硫、钙和水泥类样品为最优设计方案,从而为实际设计在线PGNAA系统提供了科学依据。     

Comparison of enhanced device response and predicted X-ray doseenhancement effects on MOS oxides

The response of MOS capacitors to low- and medium-energy X-ray irradiation is investigated as a function of gate material (TaSi or Al), oxide thickness, and electric field. The measured device response is compared to the predicted response. In comparisons of 10-keV X-ray and Co-60 irradiations of Al-gate MOS capacitors at an oxide electric field of 1 MV/cm, predictions and experiments agree to within better than 20% for oxide thicknesses ranging from 35 to 1060 nm. For capacitors with TaSi/Al gates, they agree to within better than 30% at 1 MV/cm, with the largest differences occurring for 35-nm gate oxides. At other electric fields, the disagreement between experiment and prediction increases significantly for both Al- and TaSi/Al-gate capacitors. For medium-energy (~100-keV average photon energy) X-irradiations, the enhanced device response exhibits a much stronger dependence on endpoint bremsstrahlung energy than expected from TIGERP or CEPXS/ONETRAN simulations. Implications for hardness assurance testing are discussed     

Real Time Diagnostic Data Acquisition System for the Doublet III Tokamak Fusion Experiment

The Doublet III data acquisition computer system acquires, archives, and processes over three megabytes of data from each shot of the experiment. A shot lasts 1-2 seconds and occurs every 5-6 minutes with 50-100 shots/day. The data acquisition system has been configured to efficiently handle the increasing quantity of data as new plasma instruments are added (five megabytes within a year) and to provide interactive capability during operations. The configuration is a dual CPU system with a dual port disk and bulk core memory. One CPU is devoted to acquisition and archiving while the other CPU is for analysis and interactive use. This system has enabled improved shot-to-shot processing of plasma data thus providing guidance to the physics operations team. A planned upgrade of Doublet III will require data handling of over 20 megabytes/ shot.