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161.
Uraoka Y. Eriguchi K. Tamaki T. Tsuji K. 《Semiconductor Manufacturing, IEEE Transactions on》1994,7(3):293-297
Gate oxide damage by plasma processing was evaluated using structures with various antenna lengths. The gate oxide damage by plasma processing was found to be monitored quantitatively by measuring the charge to breakdown, QBD. From the QBD measurements, we have confirmed that the degradation occurs during overetching, not in main etching. Plasma current was calculated from the decrease of QBD during the etching. The breakdown spot in the gate oxide was detected by photon emission and TEM. The LOCOS structure plays an important role for the degradation by plasma damage. In this paper, it is demonstrated that the QBD method is effective for realizing a highly reliable process against plasma damage 相似文献
162.
163.
An analytical expression for both band-to-band and band-trap-band indirect tunnelings is used to study the gate-induced drain leakage (GIDL) current of MOSFETs measured before and after hot-carrier stress. The voltage and temperature dependence of GIDL are characterized. Both results show that interface traps situated near the midgap participate in the conduction of GIDL, and band-trap-band indirect tunneling could be the major mechanism. This is further supported by the fact that the percentage increase in GIDL induced by hot-carrier stress is about the same as the corresponding increase in interface-trap density. On the other hand, under low-field conditions, trap-assisted Poole–Frenkle emission dominates over tunneling for temperatures even well below room temperature. 相似文献
164.
Y. M. Tao J. Nin G. Y. Delisle 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(10):1769-1772
GaAs Gunn diodes were fabricated for pulse source application at 8 mm wave band and operated with pulsewidths of 0.05 to 2.0 microseconds and duty cycles of 0.001 to 0.01. Peak pulse output power levels of 0.8–1.2W are achieved and the maximum available power is 1.6W with the highest efficiency of 6.5 percent. A simple and compact pulsed power combiner is also given in this paper. 相似文献
165.
This article presents the data collected from 128 court appointed psychiatric evaluations (CAPEs) and their analysis. Issues addressed are: the link between type of criminal offence and mental disorder; rate of recidivism; efficacy of the early detection and follow-up systems; inherent psychiatric dilemmas; unacceptable lacuna in information recorded in the CAPEs; and the babel of legal and psychiatric terms. We advocate that a combined effort be made by the legal and psychiatric fraternities to create a uniform and standardized CAPE. 相似文献
166.
167.
Clinical manifestations and peripheral blood lymphocyte subset changes were studied in patients with myasthenia gravis (MG) to elucidate the mechanism of clinical improvement following treatment, with thymectomy (Tx) or glucocorticoid (GC) therapy. The changes found were: 1. There was a significant increase in percentages of CD3+, CD29+ CD4+ cells and CD4/CD8 ratio and a significant decrease in percentages of CD8+ and CD16,56+ cells in patients who had never been treated with any immune therapy. 2. After Tx or GC therapy, CD3+ and CD4+, CD29+ cells were decreased, but the number CD19+ and CD16, CD56 cells did not change. 3. Tx had a special effect on CD8+ cells. In most of the patients who showed clinical improvement after Tx, CD8+ cells were increased and CD4/CD8 ratio wad decreased. 4. Anti-acetylcholine receptor (AChRAb) titers were markedly decreased after GC therapy. These results indicate that there were obvious abnormalities in cell-mediated immunity in addition to those in humoral immunity in myasthenia gravis. These abnormalities tended to be normalized after Tx or GC therapy. 相似文献
168.
169.
This prospective study evaluates the results of extracorporal shock-wave piezoelectric lithotripsy in 52 patients, 41 with radiolucent and 11 with calcified shell gallstones. The fragmentation rate was above 90% and the complication rate 31% particularly with pains or intolerance to the adjuvant dissolution therapy. At the end of the treatment, seven cholecystectomies were carried out among the 31 patients for who lithotripsy failed. After 18 months, the success rate was 23% and 12 patients only remained stone free. Nowadays, thanks to the new laparoscopic therapy, extracorporal shock-wave lithotripsy is no longer judged appropriate, especially because of its poor cost-effectiveness and high recurrence ratio. 相似文献
170.
An application of data envelopment analysis (DEA) for measuring and evaluating the operating efficiency of power plants in the Israeli Electric Corporation (IEC) is presented. Emphasis is placed on the process of screening the list of potential input and output factors and determining the most relevant ones. Special attention is given to the qualitative factor concerning air pollution, which is treated as a categorical variable. The incorporation of `standard data' is examined and the results are analyzed 相似文献