Index to 1981 NASA Tech Briefs, volume 6, numbers 1-4

Short announcements of new technology derived from the R&D activities of NASA are presented. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This index for 1981 Tech Briefs contains abstracts and four indexes: subject, personal author, originating center, and Tech Brief Number. The following areas are covered: electronic components and circuits, electronic systems, physical sciences, materials, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences

A process technology for realizing integrated inertial sensors using deep reactive ion etching (DRIE) and aligned wafer bonding

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.Includes bibliographical references (p. 89-90).by Chi-Fan Yung.S.M

DFM Techniques for the Detection and Mitigation of Hotspots in Nanometer Technology

With the continuous scaling down of dimensions in advanced technology nodes, process variations are getting worse for each new node. Process variations have a large influence on the quality and yield of the designed and manufactured circuits. There is a growing need for fast and efficient techniques to characterize and mitigate the effects of different sources of process variations on the design's performance and yield. In this thesis we have studied the various sources of systematic process variations and their effects on the circuit, and the various methodologies to combat systematic process variation in the design space. We developed abstract and accurate process variability models, that would model systematic intra-die variations. The models convert the variation in process into variation in electrical parameters of devices and hence variation in circuit performance (timing and leakage) without the need for circuit simulation. And as the analysis and mitigation techniques are studied in different levels of the design ow, we proposed a flow for combating the systematic process variation in nano-meter CMOS technology. By calculating the effects of variability on the electrical performance of circuits we can gauge the importance of the accurate analysis and model-driven corrections. We presented an automated framework that allows the integration of circuit analysis with process variability modeling to optimize the computer intense process simulation steps and optimize the usage of variation mitigation techniques. And we used the results obtained from using this framework to develop a relation between layout regularity and resilience of the devices to process variation. We used these findings to develop a novel technique for fast detection of critical failures (hotspots) resulting from process variation. We showed that our approach is superior to other published techniques in both accuracy and predictability. Finally, we presented an automated method for fixing the lithography hotspots. Our method showed success rate of 99% in fixing hotspots

Micro- and nano-electrode arrays for electroanalytical sensing

A systematic investigation of the electrochemical behaviour of two sets of microelectrode arrays, fabricated by standard photolithographic and reactive-ion etching techniques, is presented. The first set of microelectrode arrays had a constant relative centre-centre spacing of 10r (where r is the electrode radius). As a value of r was decreased, the cyclic voltammograms recorded from the array became increasingly peak-shaped, due to merging of the diffusion fields of the individual electrodes. Furthermore, it was shown that the peak current densities obtained were largest for the arrays with the smallest individual electrodes, as were the signal-to-noise ratios (SNRs). Electroplating the individuals electrodes with platinum black was also shown to increase the peak currents and the SNRs, due to an increase in the effective surface area. Sigmoidal voltammograms, which are indicative of radial diffusion, were obtained for an individual electrode radius of 25 mm but not for arrays with smaller electrodes. To obtain radial diffusion for an array of 2.5 mm electrodes, it was shown (using a second set of microelectrode arrays) that a minimum relative centre-centre spacing of 40r is required. Further enhancement of the peak current densities were obtained by decreasing the size of the individual electrodes. A series of nanoelectrode arrays were fabricated using electron-beam lithography (EBL). The voltammograms obtained from these arrays exhibited a continual increase in the recorded peak current as the individual electrodes radius was decreased to a value of 110 nm. Since EBL is a slow and costly technique, nanoimprint lithography (NIL) was investigated as an alternative method of fabricating nanoelectrode arrays and comparable results were obtained from arrays produced by EBL and NIL. A dissolved oxygen and temperature sensor incorporating a working microelectrode array was also designed and fabricated. The sector comprised a densely packed array of 2.5 mm radius electrodes and a micro-reference electrode, both of which were covered with an agarose electrolyte gel enclosed in an SU8 chamber. A thermal resistor was included for temperature compensation of the dissolved oxygen measurements. The Ag|AgCl micro-reference electrode was found to be stable for approximately 80 hours in 0.1 M KCl, with 100 nA of current passing through it. Linear calibration curves were obtained from both temperature and dissolved oxygen measurement

The Journal of Microelectronic Research 2009

https://scholarworks.rit.edu/meec_archive/1017/thumbnail.jp

Advanced Platform Systems Technology study. Volume 2: Trade study and technology selection

Three primary tasks were identified which include task 1-trade studies, task 2-trade study comparison and technology selection, and task 3-technology definition. Task 1 general objectives were to identify candidate technology trade areas, determine which areas have the highest potential payoff, define specific trades within the high payoff areas, and perform the trade studies. In order to satisfy these objectives, a structured, organized approach was employed. Candidate technology areas and specific trades were screened using consistent selection criteria and considering possible interrelationships. A data base comprising both manned and unmanned space platform documentation was used as a source of system and subsystem requirements. When requirements were not stated in the data base documentation, assumptions were made and recorded where necessary to characterize a particular spacecraft system. The requirements and assumptions were used together with the selection criteria to establish technology advancement goals and select trade studies. While both manned and unmanned platform data were used, the study was focused on the concept of an early manned space station