Ce、Mo助剂对VPO复合催化材料物性的影响

通过添加Ce、Mo助剂并采用有机溶剂法制备出一类新型的VPO催化剂。使用BET、XRD、Raman、TEM和XPS等表征手段对影响催化剂的比表面积、晶相结构考察VPO催化剂的比表面积和晶体结构。并将催化剂应用到丁烷氧化制备顺酐反应中。实验结果表明,引入Ce、Mo助剂基本上没有明显改变催化剂的比表面积,但确实改变了催化剂的物相组成、粒子形貌及表面状态等。而加入Ce、Mo助剂使催化剂的选择性也有了一定的提高。

高效率N掺杂有机电致发光器件的研制

为了改善有机电致发光器件的性能,利用Cs N_3作为N掺杂剂,以B3PYPPM为电子传输材料,制备了基于绿色磷光材料Ir(ppy)_3的高效率有机电致发光器件。针对不同N掺杂浓度和掺杂厚度的器件进行研究,最终得到最佳N掺杂器件B,器件结构为ITO/HAT-CN(5 nm)/TAPC(70 nm)/TCTA∶Ir(ppy)_3(15%,20nm)/B3PYPPM(17 nm)/B3PYPPM∶Cs N_3(10%,63 nm)/Al。实验结果表明,浓度与厚度适当的N掺杂器件能有效提高器件的电流效率和功率效率。Cs N_3作为一种高效的N掺杂剂,与电子传输材料B3PYPPM掺杂后,有效地降低了电子的注入势垒,增加了电子注入,提高了电子迁移率,改善了电子的注入和传输能力,使载流子更加平衡,从而降低了器件的开启电压和驱动电压,有效地提高了电流效率和功率效率。最佳N掺杂器件B开启电压仅为2.1 V,最大电流效率和功率效率分别为67.0 cd/A、91.1 lm/W。值得注意的是,在1 000 cd/m^2亮度下,最佳N掺杂器件B的功率效率仍能达到80.1 lm/W。

利用CsN_3n型掺杂电子传输层改善OLED器件性能的研究

为了能够有效地提高电子的注入和传输能力,改善有机电致发光器件的性能,本文利用CsN_3作为n型掺杂剂,对有机电子传输材料Bphen进行n型电学掺杂,制备了结构为ITO/MoO_3(2nm)/NPB(50nm)/Alq_3(30nm)/Bphen(15nm)/Bphen∶CsN_3(15nm,x%,x=10,15,20)/Al(100nm)的器件。实验结果表明,CsN_3是一种有效的n型掺杂剂,以掺杂层Bphen∶CsN_3作为电子传输层,可以有效地降低电子的注入势垒,改善器件的电子注入和传输能力,从而降低器件的开启电压,同时提高了器件的亮度和发光效率。在掺杂浓度为10%时器件的性能最优,开启电压仅为2.3V,在7.2V的驱动电压下,达到最大亮度29 060cd/m^2,是非掺杂器件的2.5倍以上。当驱动电压为6.6V时,达到最大电流效率3.27cd/A。而当掺杂浓度进一步提高时,由于Cs扩散严重,发光区形成淬灭中心,造成器件的效率下降。

High-performance germanium n+/p junction by nickel-induced dopant activation of implanted phosphorus at low temperature

High-performance Ge n~＋/p junctions were fabricated at a low formation temperature from 325℃ to 400℃ with a metal（nickel）-induced dopant activation technique. The obtained Ni Ge electroded Ge n＋/p junction has a rectification ratio of 5.6×10~4 and a forward current of 387 A/cm^2at -1 V bias. The Ni-based metal-induced dopant activation technique is expected to meet the requirement of the shallow junction of Ge MOSFET.

杂质分凝技术对肖特基势垒高度的调制

为降低金属或金属硅化物源漏与沟道的肖特基势垒高度以改善肖特基势垒源漏场效应晶体管(SBSD-MOSFET)的开关电流比(Ion/Ioff),采用硅化诱发杂质分凝技术(SIDS)调节NiSi/n-Si肖特基二极管(NiSi/n-Si SJD)的肖特基势垒高度,系统地研究了SIDS工艺条件如杂质注入剂量、注入能量和硅化物形成工艺对肖特基势垒高度调节的影响。实验结果表明,适当增加BF2杂质的注入剂量或能量均能显著提高有效电子势垒高度(φBn,eff),也即降低了有效空穴势垒高度(φBp,eff),从而减小反向偏置漏电流。同时,与传统的一步退火工艺相比,采用两步退火工艺形成NiSi也有利于提高有效电子势垒高度,减小反向漏电流。最后,提出了一种优化的调制肖特基势垒高度的SIDS工艺条件。

Suppressing Competitive Coordination Reaction for Ohmic Cathode Contact Using Amino-Substituted Organic Ligands and Air-Stable Metals

Ohmic cathode contact can be formed readily via coordination-activated n-doping(CAN),by co-evaporating air-stable metals(e.g.,silver)and organic ligands with coordination sites.It has been proposed that increasing the nucleophilicity of the main binding site of a ligand is essential for reducing the work function of the doped films.

Deep Eutectic Solvent-assisted Synthesis of Nitrogen-doped Carbon Quantum Dots for Cell Imaging

Carbon quantum dots(CQDs)are widely used in fluorescence imaging due to their negligible toxicity,low-cost and excellent Huorescence properties.The fluorescence properties of CQDs are greatly a fleeted by the synthesis method,passivation agent and reaction media.In this study,the nitrogen-doped CQDs(N-CQDs)were synthesized by a facile microwave-assisted method with citric acid(CA)as a carbon source and deep eutectic solvents as a N-dopaiit as well as the reaction solvent.After detailed characterizations,the as-prepared N-CQDs exliibited near spherical morphology with an average size of(2.64±0.55)nm.Besides,the abundant hydrophilic limctional groups including hydroxyl,carboxyl,amine and quaternary-ammonium were present on the surface of the N-CQDs.TheN-CQDs displayed the excitation-dependent fluorescence feature under the excitation wavelength of 350—80 nm.Moreover,the N-CQDs could be efficiently uptaken by RAW264.7 cells and emitted bright green light.Meanwhile,the resultant N-CQDs showed the low cytotoxicity in living cells,suggesting the great potential in bio-imaging applications.

路易斯碱负离子掺杂有机半导体:原理、应用和展望

掺杂是改善有机半导体载流子浓度和电荷输运能力的有效方法.路易斯碱负离子电子转移掺杂有机半导体,逐渐发展成为了一种温和、可控和可溶液加工的n型掺杂方法,并在有机光电器件中展现出较好的应用.本综述旨在探讨路易斯碱负离子和n型半导体之间的电子转移机制及其影响因素,总结基于该策略开发的界面材料和活性层掺杂等方面的应用,并展望其未来的发展方向.

SBH adjustment characteristic of the dopant segregation process for NiSi/n-Si SJDs

By means of analyzing theⅠ-Ⅴcharacteristic curve of NiSi/n-Si Schottkyjunction diodes（NiSi/n-Si SJDs）, abstracting the effective Schottky barrier height（φ_（B,eff）） and the idealfactor ofNiSi/n-Si SJDs and measuring the sheet resistance of NiSi films（R_（NiSi））,we study the effects of different dopant segregation process parameters,including impurity implantation dose,segregation annealing temperature and segregation annealing time,on theφ_（B,eff） of NiSi/ n-Si SJDs and the resistance characteristic of NiSi films.In addition,the changing rules ofφ_（B,eff） and R_（NiSi） are discussed.

Adjustment of NiSi/n-Si SBH by post-silicide of dopant segregation process

The post-silicide of dopant segregation process for adjusting NiSi/n-Si SBH（Schottky barrier height）is described.Adopting the analysis of the I–V characteristic curve and extrapolating the SBH of NiSi/n-Si Schottky junction diodes（NiSi/n-Si SJDs）,the effects of different of process parameters dopant segregation,including segregation anneal temperature and dopant implant dose,on the properties of the NiSi/n-Si SJDs have been studied,and the corresponding mechanisms are discussed.

The effect of δ-doping and modulation-doping on Si-doped high Al content n-Al_xGa_(1-x)N grown by MOCVD

The effect of periodic delta-doping and modulation-doping on high Al content n-AlxGa1-xN （x = 0.55） epilayers grown by MOCVD has been investigated. Measured by XRD, AFM, contactless sheet resistance, and Hall-effect tests, 8-doped and modulation-doped n-Alx Ga1-xN have better crystal quality, surface morphology and electrical properties as compared with uniformly-doped n-AlxGa1-xN. These improvements are attributed to the SiNx growth mask induced by δ-doping layers and the dislocation-blocking effect induced by both growth techniques. In addition, due to the broadened doping profile ascribed to enhanced dopant diffusion at high growth temperatures （1150 ℃） ofn-Al0.55 Ga0.45N, modulation-doped n-Al0.55 Ga0.45N has similar properties as 8-doped n-Al0.55 Ga0.45N.