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宽带碲基掺铒光纤放大器掺杂特性的理论研究   总被引:1,自引:1,他引:0  
对WDM系统中宽带碲基掺铒光纤放大器(EDTFA)多信道增益谱特性的研究表明,在给定泵浦方式、泵浦功率和光纤长度的工作条件下,碲基掺铒光纤中铒掺杂浓度对EDTFA各信道信号增益的影响并不相同,相比于长波长信道,短波长信道的信号增益随着光纤中铒掺杂浓度的提高更易趋于饱和及快速衰减状态,同时信号增益谱向长波长方向萎缩.  相似文献
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短沟道效应是MOS器件特征尺寸进入Sub-100 nm后必须面对的关键挑战之一.Halo结构能够有效地抑制短沟道效应,合理的Halo区掺杂分布会极大地改善小尺寸器件性能.文中采用器件和工艺模拟工具ISE-TCAD研究形成Halo结构的工艺参数对器件性能的影响,并进行优化.分析表明,Halo注入角度、能量和剂量的增大会提高器件的阈值电压和开关比,降低泄漏电流和阈值漂移,有效抑制SCE、DIBL效应,但同时也会部分地降低驱动能力,即Halo注入参数对器件性能的影响不是简单的线性关系,需要根据具体条件寻求优化值.  相似文献
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采用解析的方法计算了在基区掺杂为高斯分布,Ge组分分布为三角形分布和矩形三角形分布时基区内建电场的变化情况.重新拟合了价带有效态密度公式,并在计算内建电场时考虑了导带有效态密度的影响.发现加入Ge组分后引起的导带有效态密度变化、价带有效态密度变化以及禁带宽度变窄量变化对基区内建电场的影响要大于掺杂对内建电场的影响.Ge组分为三角形分布时,在总的Ge组分一定的条件下,内建电场从发射结到集电结逐渐变大.在任一给定位置x处,内建电场随着Ge组分的增加而增大.当Ge组分分布为矩形三角形分布时,对于给定的Ge组分转折点x1,基区内建电场从发射结到集电结缓慢地增大.在Ge组分恒定的区域,内建电场变化甚微,在Ge组分为线性缓变区域的同一位置x处,内建电场随Ge组分转折点x1的增大而缓慢地增大.此外,在x1附近内建电场变化有一个很大的陡坡.  相似文献
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Hg1−xCdxTe films were grown liquid phase epitaxially from tellurium rich solutions containing up to 10 at. % of the group V elements P, As, Sb, and Bi. Chemical analysis of the Te growth solutions and the films was carried out in conjunction with extensive Hall effect measurements on the films subsequent to various annealing treatments under Hg rich and Te rich conditions. Despite the presence of a large concentration of the group V elements in the Te source solution, the maximum concentration of these elements incorporated into the liquid phase epitaxially grown Hg1-xCdxTe appears to vary from <1015cm−3 for Bi up to 1017cm−3 for phosphorus and As implying a distribution coefficient varying from <10−5 for Bi up to 10−3 for P at growth temperature of ∼500° C. This low value of the distribution coefficient for group V elements for growths from Te rich solutions contrasts with the moderately high values reported in the literature to date for growth from Hg rich solutions as well as pseudobinary solutions (Bridgman growth). The widely differing distribution coefficients and hence the solubility of the group V elements for Hg rich and Te rich liquid phase epitaxial solutions is explained on the basis that the activity coefficient of the group V elements in Te rich solutions is probably orders of magnitude lower than it is in Hg rich solutions. Finally, the results of the anneals at 200° C under Hg saturated conditions with and without a 500° C Hg saturated preanneal have indicatedn top conversion in many of the films attesting to the amphoteric behavior of the group V elements in LPE grown Hg1−xCdxTe(s) similar to the previously reported behavior of P in bulk grown Hg0.8Cd0.2Te.  相似文献
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