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1.
用550eV的低能量Ar^ 离子束轰击n-MOSFET(n沟金属-氧化物-半导体场效应晶体)芯片的背面,以改善其饱和区的直流特性(如跨导、阈值电压和表面有效迁移率)以及低频噪声等.结果表明,随着轰击时间的增加,跨导和沟道表面有效迁移率先增大后减小,阂值电压先减小后增大,而低频噪声在轰击后明显减小.实验证明,上述参数的变化是硅-二氧化硅界面的陷阱密度和二氧化硅中固定电荷密度在轰击后变化的结果。  相似文献   

2.
在完成超高频小功率晶体管的芯片和上部铝电极的制备工艺后,采用低能量氩离子束轰击芯片背面,能有效地降低其高频及低频噪声系数、提高其特征频率和电流放大系数。实验结果表明,晶体管低频噪声系数的下降与硅-二氧化硅界面的界面态密度的减小有关,而其高频噪声系数的下降是特征频率和电流放大系数增加的结果。  相似文献   

3.
Ultra-Violet Laser Ablation Microprobe (UVLAMP) extraction technique enables the direct investigation of Ar-Ar age prorde in crystals, and yields more information on rates and durations of geological process than conventional single time snapshots. Phlogopite flakes from lamprophyre at Pishan dyke in western Kunlun were dated by using an UV laser (λ= 213 nm) microprobe with spot analyses. The results show good agreement with those from the conventional ^40Ar/^39Ar step heating experiments. This indicates that the Ar isotopes are distributed homogenously in the phlogopite and the UVLAMP can be a powerful tool in the study of thermal history.  相似文献   

4.
The 40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian (401 Ma) and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian (381 Ma). The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian (370─364 Ma). The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.  相似文献   

5.
用基因芯片检测鉴定离子束辐照下水稻中的差异表达基因(DEGs).结果共检测到26个上调和6个下调的差异表达基因.共表达网络分析(RiceNET)表明,这些基因都存在着直接或间接的互作网络,暗示水稻存在着以前没有充分认识的基因网络.为进一步研究植物应答离子束辐照候选基因提供了基础.  相似文献   

6.
在Ar+H2气氛下,用RF磁控溅射法在室温下制备Al掺杂的ZnO(AZO)薄膜,研究H2/(Ar+H2)流量比对薄膜结构和光电性能的影响。结果表明,在沉积气氛中引入H2可以提高AZO薄膜的结晶质量,降低AZO薄膜的电阻率,提高其霍尔迁移率和载流子浓度;H2/(Ar+H2)流量比为5%时,AZO薄膜的最小电阻率为1.58×10-3Ω.cm,最大霍尔迁移率和载流子浓度分别为13.17cm2.(V.s)-1和3.01×1020 cm-3;AZO薄膜在可见光范围内平均透光率大于85.7%。  相似文献   

7.
罗薇  林合山 《江西科学》2010,28(1):67-71
在硅酸盐玻璃基质上用Ag+-Na+离子交换法制备光波导。采用棱镜耦合法测量光波导有效折射率,并用IWKB法计算光波导折射率分布曲线。得到了交换工艺条件和光波导性能之间的关系,讨论了Ag+离子浓度、交换温度和扩散时间对光波导制备工艺的影响。  相似文献   

8.
9.
The petrology and mineral assemblages of blueschists in the Gangmar, central Qiangtang, northern Tibet were examined, which indicates that the metamorphic condition is high-pressure low-temperature. In this note, we reported the 40Ar/39Ar dating results of glaucophane from two blueschist samples. Their apparent ages are (275.0± 1.3) Ma and (287.6± 2.3) Ma and similar isochron ages are (275.0± 0.9) Ma and (282.4± 0.8) Ma, respectively. These isotopic datings show the high-pressure metamorphism occurring in Lower Permian. The ages also coincide with the evolution of Palaeo-Tethys ocean in Late Palaeozoic.  相似文献   

10.
The40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian (401 Ma) and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian (381 Ma). The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian (370-364 Ma). The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.  相似文献   

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