直拉硅单晶中的流动图形缺陷

用Secco腐蚀液对直径15 0 mm p型(10 0 )直拉硅单晶片进行择优腐蚀后,得到了流动图形缺陷(FPDs) ,并通过原子力显微镜(AFM)对其微观结构进行观察.实验发现,在FPDs缺陷的尖端存在有几百纳米的由(111)面构成的八面体空洞,这与Takeno等人的实验结果相反,他们认为FPD的端部是间隙型的位错环;实验还发现,FPD端部的空洞随腐蚀时间延长会逐渐变为圆形的浅坑直至最后消失     

A PNPN tunnel field-effect transistor with high-k gate and Iow-k fringe dielectrics

A PNPN tunnel field effect transistor(TFET) with a high-k gate dielectric and a low-k fringe dielectric is introduced.The effects of the gate and fringe electric fields on the TFET’s performance were investigated through two-dimensional simulations.The results showed that a high gate dielectric constant is preferable for enhancing the gate control over the channel,while a low fringe dielectric constant is useful to increase the band-to-band tunneling probability.The TFET device with the proposed structure has good switching characteristics,enhanced on-state current,and high process tolerance.It is suitable for low-power applications and could become a potential substitute in next-generation complementary metal-oxide-semiconductor technology.     

量子计算关键技术及应用发展分析

量子计算具备可能超越经典计算的潜在能力,近年来在技术研究、应用探索及产业生态培育等方面取得诸多进展,整体发展进入快车道,已成为全球多国科研布局与投资热点。重点梳理分析量子计算关键技术研究进展、应用探索开展态势和产业生态培育等,并对未来发展趋势进行展望。     

红外探测器微结构的HREM观察

采用定位横断面制样的高分辨电子显微技术（ＨＲＥＭ）观察了Ｐ＋－Ｓｉ０．６５Ｇｅ０．３５／Ｐ－Ｓｉ异质结内光发射红外探测器的微结构．该器件光敏区是由３层Ｐ＋－Ｓｉ０．６５Ｇｅ０．３５和２层ＵＤ－Ｓｉ（未掺杂硅）组成,Ｓｉ０．６５Ｇｅ０．３５／ＵＤ－Ｓｉ层间界面不明锐,有一个由于Ｇｅ原子不均匀扩散造成的过渡带．这个过渡带缓和了界面的失配应力,因而未观察到界面晶体缺陷和严重的晶格畸变．在光敏区边缘有呈倒三角形的缺陷区,缺陷的主要类型为层错和微孪晶．层错在（１　１１）面上,而微孪晶的厚度约为２～４晶面间距,其孪晶     

GaAs/SiO_2超晶格的制备和Raman光谱研究

我们采用射频磁控溅射方法在 p- Si衬底上成功地制备出四周期的非晶 Ga As/Si O2超晶格 ,并取得其高分辨率电镜像。以 80 0℃快速退火方法使超晶格中非晶的 Ga As层局部晶化 ,利用 Raman散射谱研究了其结构变化。     

降低硅片表面微粗糙度的预氧化清洗工艺

利用原子力显微镜研究了预氧化清洗工艺对清洗后的硅片表面微粗糙的影响,并通过建立表面氧化过程的分子模型和氧化层模型来进行相应的机理分析.结果表明,硅片表面在含有氧化剂H2O2的溶液中生成一层氧化层后,能基本消除OH-对硅片表面的各向异性腐蚀,清洗后的表面微粗糙度比清洗前小,并且随SC-1清洗过程中NH4OH浓度的增大而减小.     

Mobility enhancement of strained GaSb p-channel metal oxide semiconductor field-effect transistors with biaxial compressive strain

Various biaxial compressive strained GaSb p-channel metal–oxide–semiconductor field-effect transistors(MOSFETs)are experimentally and theoretically investigated. The biaxial compressive strained GaSb MOSFETs show a high peak mobility of 638 cm~2/V·s, which is 3.86 times of the extracted mobility of the fabricated GaSb MOSFETs without strain.Meanwhile, first principles calculations show that the hole effective mass of Ga Sb depends on the biaxial compressive strain.The biaxial compressive strain brings a remarkable enhancement of the hole mobility caused by a significant reduction in the hole effective mass due to the modulation of the valence bands.     

Heteromaterial-gate line tunnel field-effect transistor based on Si/Ge heterojunction

A Si/Ge heterojunction line tunnel field-effect transistor(LTFET) with a symmetric heteromaterial gate is proposed.Compared to single-material-gate LTFETs, the heteromaterial gate LTFET shows an off-state leakage current that is three orders of magnitude lower, and steeper subthreshold characteristics, without degradation in the on-state current. We reveal that these improvements are due to the induced local potential barrier, which arises from the energy-band profile modulation effect. Based on this novel structure, the impacts of the physical parameters of the gap region between the pocket and the drain, including the work-function mismatch between the pocket gate and the gap gate, the type of dopant, and the doping concentration, on the device performance are investigated. Simulation and theoretical calculation results indicate that the gap gate material and n-type doping level in the gap region should be optimized simultaneously to make this region fully depleted for further suppression of the off-state leakage current.     

通过式固相萃取/超高效液相色谱-串联质谱法快速测定动物源性食品中安乃近代谢物残留量

建立了通过式固相萃取/超高效液相色谱-串联质谱(UPLC-MS/MS)快速测定动物源性食品中4-甲氨基安替比林(MAA)、4-氨基安替比林(AA)、4-甲酰氨基安替比林(FAA)和4-乙酰氨基安替比林(AAA) 4种安乃近代谢物的方法。样品采用乙腈提取,PRiME HLB固相萃取柱净化,在ACQUITY BEH C_(18)色谱柱上以乙腈和0.1%甲酸水溶液为流动相梯度洗脱,超液相色谱-串联质谱MRM方式进行定量分析。结果表明,4种化合物在0.5～50μg/L范围内线性关系良好,相关系数(r)大于0.996,方法的检出限(LOD)为2μg/kg,定量下限(LOQ)为5μg/kg。4种化合物在3个加标水平(5、10和50μg/kg)下的回收率为75.1%～115%,相对标准偏差(RSD)为1.6%～7.4%。该方法简单、快速、准确,可实现动物源性食品中安乃近代谢物的快速测定。