Tool Qualification Research Articles

Accident Management in VVER-1000

The present paper deals with the investigation study on accident management in VVER-1000 reactor type conducted in the framework of a European Commission funded project. The mentioned study involved both experimental and computational fields. The purpose of this paper is to summarize the main findings from the execution of a wide-range analysis focused on AM in VVER-1000 with main regard to the qualification of computational tools and the proposal for an optimal AM strategy for this kind of NPP.

Qualification of rapid prototyping tools: proposition of a procedure and a test part

Rapid prototyping machines are becoming faster at manufacturing machine tools. The processes of quality assurance impose the qualification of the production devices. A procedure and a test part are proposed for that purpose; intended for the family of processes of point-by-point layer manufacturing. Existing test parts only permit benchmarking and comparisons between machines: their capacity can be evaluated, but the test part analysis does not make it possible to establish the link between noted defects and their causes. The proposed process and test part permit the identification of the defects and whether their origins are machine or material linked. This paper describes the approach used to design the test part. Some preliminary measures were made on a test part, in order to discuss procedure and measurements.

Neutronics design and supporting experimental activities in the EU

Neutronics and nuclear data have an essential role in the development programme leading to the realization of a fusion power plant. A well-qualified nuclear database and validated computational tools are required in the nuclear design of fusion devices for reliable neutronics and activation calculations with the associated uncertainties. The EU is conducting a large effort on neutronics and nuclear data for fusion applications. According to the fusion strategy, the efforts focus on the development and qualification of computational tools and nuclear data required for design analyses of ITER, in particular for the test blanket modules (TBM), and of IFMIF. A major effort is devoted to integral experiments with the objective to provide the experimental database for testing the nuclear data and validating neutronics design calculations. The paper provides an overview of the nuclear design activities conducted in the EU on the development of TBMs for ITER and the layout of material test modules for IFMIF. The focus is on the supporting neutronics efforts including the experiments for validating design calculations and nuclear data with associated uncertainties. The recent achievements will be presented and recommendations will be given for further development efforts on neutronics and nuclear data for fusion applications.

In-Line Phase and Texture Control in Microelectronics Industry

We present the principles of operation and a summary of results from in-fab automated X-ray diffraction (XRD) metrology in support of copper damascene roduction. The automated XRD tools (an example is shown in Figure 1) are capable of rapid mapping of 300 mm wafers (with a throughput rate of 40 wafers/hour) of quantitative information about the film crystallographic composition, texture and thickness with a spatial resolution down to 30 microns. Microstructure control plays an increasingly important role in improving the performance and reliability of ULSI devices that use the damascene copper technology at 130 nm node and below. The problems related to delamination, stress voiding, and electromigration failures could be mitigated by the selection of proper materials, processing methods, and manufacturing tools. The optimum process would result in a tailored microstructure of barrier/seed/electroplated copper aggregate. At the same time, the microstructure could be used as an internal sensor, sensitive to process excursions and providing guidance for corrective actions. The texture and crystallographic phase data can be used as a direct measure of the deposition process in terms of film quality, reproducibility, and stability over time. The spatial distribution of crystallographic texture and phase can be measured on a single wafer in order to check wafer uniformity. More importantly, the same measurements can be carried out at predetermined intervals on wafers from a single deposition tool, and the results used to create a database that can be applied to trend charting and tool qualification. Examples of microstructure control in damascene copper processing include: process development and qualification, process control and stability, process excursion and post maintenance stability, deposition tool qualification, and on-line R&D. The examples of texture control will refer to materials and processes typical of damascene copper technology for ULSI. A typical processing route includes the PVD deposition of a barrier layer and copper seed layer, followed by copper electroplate, anneal and chemical- mechanical planarization. All the processing steps affect the texture of annealed copper, and therefore affect directly the performance of interconnects. We will also present examples of application to processing of metal gates (NiSi films) and ferroelectric non-volatile memory (PZT films).

Experimental evaluation of software development tools for safety-critical real-time systems

Since the early years of computing, programmers, systems analysts, and software engineers have sought ways to improve development process efficiency. Software development tools are programs that help developers create other programs and automate mundane operations while bringing the level of abstraction closer to the application engineer. In practice, software development tools have been in wide use among safety-critical system developers. Typical application areas include space, aviation, automotive, nuclear, railroad, medical, and military. While their use is widespread in safety-critical systems, the tools do not always assure the safe behavior of their respective products. This study examines the assumptions, practices, and criteria for assessing software development tools for building safety-critical real-time systems. Experiments were designed for an avionics testbed and conducted on six industry-strength tools to assess their functionality, usability, efficiency, and traceability. The results some light on possible improvements in the tool evaluation process that can lead to potential tool qualification for safety-critical real-time systems.

Texture Control in Manufacturing of ULSI Devices

The rapid adoption of damascene copper processing has brought about an increased need to understand and control microstructure in the barrier, seed and electroplated copper layers during manufacture. We will discuss an in-line, x-ray diffraction based metrology for rapidly characterizing thin film polycrystalline microstructures on 300 mm silicon wafers in terms of crystallographic texture, phase composition, and film thickness. The microstructure control plays an increasingly important role in improving the performance and reliability of ULSI devices that use the damascene copper technology at 0.13-µm node and below. The problems related to delamination, stress voiding, and electromigration failures could be mitigated by the selection of proper materials, processing methods, and manufacturing tools. The optimum process would result in a tailored microstructure of barrier/seed/electroplated copper aggregate. At the same time, the microstructure could be used as an internal sensor, sensitive to process excursions and providing guidance for the corrective actions. The texture and crystallographic phase data can be used as a direct measure of the deposition process in terms of film quality, reproducibility, and stability over time. The spatial distribution of crystallographic texture and phase can be measured on a single wafer in order to check wafer uniformity. More importantly, the same measurements can be carried out at predetermined intervals on wafers from a single deposition tool, and the results used to create a database that can be applied to trend charting and tool qualification. Examples of microstructure control in damascene copper processing include: process development and qualification, process control and stability, deposition tool qualification, and on-line R&D. Examples of texture control will refer to materials and processes typical of damascene copper technology for ULSI. A typical processing route includes the PVD deposition of a barrier layer and copper seed layer, followed by copper electroplate (EP), anneal, and chemical-mechanical planarization (CMP). All the processing steps affect the texture of annealed copper, and therefore affect directly the performance of interconnects.

Design of a 2-D Cementation Experiment in Porous Medium Using Numerical Simulation

The validation and qualification of reactive transport simulation tools has motivated the design and simulation, at a laboratory scale, of an experiment in which flow, advective/dispersive transport of solutes and physicochemical transformation affecting a porous medium are strongly coupled. Several possible experimental setups (or designs) have been evaluated using numerical simulation. The selected experimental design involves the successive precipitation and perforation of a clogging obstacle composed of calcium oxalate. Before an experiment can actually be conducted, this problem is proposed as a numerical benchmark for reactive transport codes and simulated using the coupled reactive transport code Hytec (CIG-Ecole des mines, France).

Investigation into the accuracy of a proposed laser diode based multilateration machine tool calibration system

Geometric and thermal calibration of CNC machine tools is required in modern machine shops with volumetric accuracy assessment becoming the standard machine tool qualification in many industries. Laser interferometry is a popular method of measuring the errors but this, and other alternatives, tend to be expensive, time consuming or both. This paper investigates the feasibility of using a laser diode based system that capitalises on the low cost nature of the diode to provide multiple laser sources for fast error measurement using multilateration. Laser diode module technology enables improved wavelength stability and spectral linewidth which are important factors for laser interferometry. With more than three laser sources, the set-up process can be greatly simplified while providing flexibility in the location of the laser sources improving the accuracy of the system.

8.6.2 Systems Engineering – Consumer and Infrastructure Approaches

AbstractSystems Engineering processes increase in complexity for infrastructure applications compared with consumer. The level of testing documentation, subassembly qualification and verification of simulation tools are important for infrastructure systems but are of minimal value for consumer systems. Requirements tracking and flow‐down from the customer performance specifications are more detailed and costly for infrastructure systems. Infrastructure systems that are based upon stable technologies, such as buildings or utilities usually do not use Systems Engineering processes.

Imaging and Analytical Challenges for Nanoscale Semiconductor Technology: Breakthrough Needs for Development and Manufacturing

The complexity of today’s commercial semiconductors has contributed to tremendous gains in device performance; millions of transistors are now packed into each square centimeter of silicon. The reduction of scale occurring within the semiconductor industry places extraordinary new demands on transmission electron microscopy: TEM is becoming a required precision measurement tool for manufacturing and a necessary analytical tool for R&D and failure analysis support. This paper reviews the industry’s needs for advanced TEM sample preparation, imaging and microanalysis and outlines the challenges presented to the TEM community as device dimensions continue along the National Technology Roadmap.In the semiconductor industry, TEM is applied to process debugging, yield engineering, tool qualifications, single-bit failure analyses, and new process development. A large fraction of the analysis effort focuses on transistor, metal, interconnect and dielectric structures grown on and into the Si wafer. Fig. 1 shows a TEM image of a multilayer metal in a near-current generation microprocessor to illustrate the scale and nature of complexity.

Plasma generators for re-entry simulation

The qualification of thermal protection systems (TPS) and numerical design tools for re-entry vehicles and space probes requires the ability to understand and duplicate the prevailing complex physico-chemical phenomena, including thermal and chemical nonequilibrium near the surface of a body that enters the atmosphere of the Earth or another celestial body. At the Institut fur Raumfahrtsysteme of the University of Stuttgart, four plasma wind tunnels (PWK1-4) are in operation to simulate the thermal, aerodynamic, and chemical loads on the surface of a space vehicle. Three different plasma sources have been developed for this purpose: 1) a magnetoplasmadynamic generator for the simulation of the highenthalpy and low-pressure environment during the first phase of re-entry, 2) a thermal arcjet device for the follow-on flight path at moderate specific enthalpies and higher stagnation pressures, and 3) an inductively heated generator for basic materials experiments over a wide range of specific enthalpies and pressures. Special efforts were made to avoid electrode erosion to preclude impairing the erosion and catalytic behavior of TPS materials. A detailed description of these plasma generators and an overview of the simulation regions and operation areas of the plasma wind tunnels are presented.

Qualification of tools for overlay measurement on processed wafers

In this paper we present two new methodologies to verify the accuracy of a measurement tool. The dependence of the measurements on substrates and the correlation with the same patterns with the same misalignment is shown. Theusefulness and reliability of the methods is proved by examples on commercially available equipment.