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1.
研究了掺氮直拉硅单晶(NCZ)中氮在高温退火过程中对氧沉淀的影响.通过不同温度高温退 火后,测量氧沉淀的生成量和观察硅片体内微缺陷(BMD)密度与高温形核时间的变化关系 ,同时用透射电子显微镜(TEM)观察氧沉淀及相关缺陷的微观结构.实验结果表明高温退火后 氮对硅中氧沉淀形核有明显的促进作用,在相同退火条件下NCZ硅中BMD密度要远远高于相应 的普通直拉硅.这是由于氮在高温下与氧反应形成氮氧复合体(N-V-O)促进了氧沉淀的形核 ,而且TEM的结果表明氧沉淀的形态都是平板状,周围存在应力场. 关键词: 直拉硅 掺氮 氧沉淀  相似文献   

2.
通过对比研究重掺砷直拉硅片和轻掺n型直拉硅片经过低温(450—800℃)和高温(1000℃)两步退火的氧沉淀行为,阐明了低温退火对重掺掺砷直拉硅片的氧沉淀形核的作用.研究指出:重掺砷硅片在450℃和650℃退火时的氧沉淀形核比在800℃退火时更显著,这与轻掺硅片的情况截然相反;此外,与轻掺硅片相比,重掺砷硅片在450℃和650℃退火时氧沉淀的形核得到增强,而在800℃退火时氧沉淀的形核受到抑制.分析认为,重掺砷硅片在450℃和650℃退火时会形成砷-空位-氧(As-V-O)复合体,它们促进了 关键词: 重掺砷直拉硅片 氧沉淀形核 低温退火  相似文献   

3.
吉川  徐进 《物理学报》2012,61(23):369-373
系统研究了点缺陷对晶体硅中氧沉淀生成的影响,及点缺陷和氧沉淀对重掺硼直拉硅单晶p/p+外延片中铜沉淀的影响.样品先在不同的气氛下进行1250℃/60 s快速热处理,随后在750℃/8 h+1050℃/16 h常规热处理过程中引入铜沾污.通过腐蚀结合光学显微镜研究发现,以O2作为保护气氛时,p+衬底中的沉淀密度较小,以Ar和N2作为保护气氛时,重掺硼p+衬底中生成了高密度的沉淀,且在上述所有样品的外延层中均无缺陷生成.研究认为,以O2作为保护气时引入的自间隙硅原子(SiI)可以抑制沉淀的形成,而以Ar和N2作为保护气氛时引入的空位则会促进沉淀的生成,这是导致此差异的主要原因.另外,研究还发现,p/p+外延结构能很好地吸除硅片中的铜杂质,从而保持了外延层的洁净.  相似文献   

4.
对不同气氛下高温退火非掺杂磷化铟(InP)材料的电子辐照缺陷进行了研究. 除铁受主外,磷化铁(FeP2)气氛下退火后的InP中辐照前没有深能级缺陷,而辐照后样品的热激电流谱(TSC)中出现了5个较为明显的缺陷峰,对应的激活能分别为0.23 eV, 0.26 eV, 0.31 eV, 0.37 eV和0.46 eV. 磷(P)气氛下退火后InP中的热生缺陷较多,电子辐照后形成的缺陷具有复合体特征. 与辐照前相比,辐照后样品的载流子浓度和迁移率产生显著变化. 在同样的条件下,经FeP2 气氛下高温退火后的InP样品的辐照缺陷恢复速度较快. 根据这些现象分析了缺陷的属性、快速恢复机理和缺陷对材料电学性质的影响. 关键词: 磷化铟 电子辐照 缺陷  相似文献   

5.
钨酸铅晶体中的偶极缺陷   总被引:3,自引:0,他引:3       下载免费PDF全文
冯锡淇  邓棠波 《物理学报》2003,52(8):2066-2074
在用阻抗谱研究PbWO4(PWO)晶体的介电特性时发现,掺La3+的PW O晶体中存在典型的介电弛豫现象,它被归因于La3+进入Pb位并与铅空位VPb缔合 成偶极缺陷.这一结果不仅清楚地证明了PWO晶体中铅空位的存在,而且表明阻抗谱测试可以成为PWO晶体微结构研究的有力工具.以阻抗谱测试为主要工具,结合光吸收谱(包括红外谱)和x射线光电子能谱,阐明了在异价掺杂离子(3+,4+,5+以及3+和5+双掺)掺杂的PWO晶体中 关键词: 钨酸铅 偶极缺陷 异价掺杂 退火效应  相似文献   

6.
陆昉  孙恒慧  黄蕴  盛篪  张增光  王梁 《物理学报》1987,36(6):745-751
本文对高温电子辐照硅中产生的缺陷进行了研究,发现缺陷的引进率随电子辐照温度的增加而增加,在达到极值温度Tm后,缺陷的引进率将随之而下降,Tm值与缺陷的退火激活能有关。E3缺陷(Ec—0.36eV)浓度在高温电子辐照中显著增加,在330℃高温电子辐照时,E3缺陷浓度为室温电子辐照的6倍。研究结果表明,E3缺陷的可能结构为与多空位和氧有关的复合体。 关键词:  相似文献   

7.
中子辐照直拉硅中的本征吸除效应   总被引:8,自引:2,他引:6       下载免费PDF全文
对经中子辐照的直拉硅中的本征吸除效应进行了研究.结果表明:经中子辐照后,直拉硅片经一步短时退火就可以在硅片表面形成完整的清洁区.清洁区宽度受辐照剂量和退火温度所控制,清洁区一旦形成,就不随退火时间变化.大量的缺陷在中子辐照时产生,并同硅中氧相互作用,加速了硅片体内氧的沉淀,是快速形成本征吸除效果的主要因素,从而把热历史的影响降到次要地位 关键词: 本征吸除 中子辐照 直拉硅  相似文献   

8.
杨义斌  龚宇  刘才林  罗阳明  陈平 《物理学报》2016,65(6):66701-066701
核能是一种新型能源, 其开发和利用对氢同位素分离和纯化提出了迫切要求. BaZrO3基钙钛矿氧化物是一种有效分离纯化氢同位素的材料, 本文采用高温固相法制备了BaZr1-xYxO3-δ (0≤ x ≤0.3)系列样品, 射线衍射光谱分析表明Y的最大掺杂浓度在0.24-0.26之间. 在600 ℃干燥氢气气氛下, 由电化学阻抗谱测试可知, 掺20 mol%Y 的BaZr1-xYxO3-δ样品电导率可达σ =0.00150 S/m, 较BaZrO3基质材料的电导率高接近两个数量级. 利用热释光谱和发射光谱研究了系列样品缺陷类型, 结果表明BaZrO3基质材料存在两种对质子传导有利的氧空位(Vo..); 当掺入Y 后, 除氧空位之外, 样品还出现了带负电的质子俘获型缺陷YZr', 且 YZr'缺陷的数量随着Y掺杂浓度增加而增多; 同时出现了缺陷陷阱深度变浅导致对质子捕获能力降低的现象, 有利于提高质子导电性. 本文通过发射光谱和热释光谱相结合, 有效地研究了BaZr1-xYxO3-δ材料的缺陷类型.  相似文献   

9.
采用提拉法生长了Cr单掺和Cr,Mg共掺Al2O3晶体,后者具有900—1600nm的宽带吸收.研究了该吸收带在不同气氛、不同温度退火下的变化规律.通过建立合理的晶格缺陷模型,成功地解释了所有的实验结果,并确定Cr,Mg共掺Al2O3晶体红外波段宽吸收带属于八面体格位中的Cr4+离子. 关键词: 4+离子')" href="#">Cr4+离子 八面体格位 晶格缺陷  相似文献   

10.
刘建军  张万林  张光寅 《物理学报》1996,45(11):1852-1858
根据铌酸锂晶体本征缺陷的Li空位模型,提出了掺镁铌酸锂晶体的缺陷结构模型;计算出了掺镁铌酸锂晶体中LiO,Nb5的含量、[Li]/[Nb]比以及晶体的密度随掺镁浓度的变化关系.计算结果与文献中报道的实验结果相符合 关键词:  相似文献   

11.
The distribution and etching rate of flow pattern defects (FPDs) in germanium- doped Czochralski (GCZ) silicon (Si) wafers with light and heavy dopants—either boron (B) or phosphorus (P)—have been investigated. In the lightly doped (both B and P) Czochralski (CZ) Si crystals, the FPD densities in GCZ Si decrease with the increase of Ge concentration. In the heavily B-doped GCZ Si crystals, the FPDs are denser compared with the heavily B-doped CZ Si, whereas the reverse is true in the heavily P-doped GCZ Si and CZ Si crystals. It is also shown that the etching rates in the lightly doped CZ Si crystals can be slightly enlarged by the Ge doping. It is proposed that, in lightly doped GCZ Si, Ge doping could consume free vacancies and thus form high-density but small-sized voids, while the stress compensation induced by B and Ge atoms could increase the vacancy concentration in heavily B-doped GCZ Si, leading to sparse and large-sized voids.  相似文献   

12.
首次报道了PbWO4:Sb的光谱特性,包括透射谱和Xe灯光源激发的发射谱与激发谱.掺Sb具有增强绿光带、抑制红光带并大幅度提高光产额的效果.通过与空气退火PWO发光的比较,对绿光带的起因、Sb掺杂的作用也进行了简要的讨论.  相似文献   

13.
The effect of annealing atmosphere, temperature and aging on the photoluminescence of pure and Li-doped ZnO thin films has been investigated. Annealing the pure ZnO in N2 and He above 800 °C results in green emission centered at ca. 500 nm; however annealing in air red-shifts the green emission to 527 nm. The visible emission of the Li-doped ZnO is found to be largely dependent on the annealing atmosphere. Warm-white photoluminescence with a broad emission band covering nearly the whole visible spectrum is obtained for the Li-doped ZnO films annealed in helium. The substitutional and interstitial extrinsic point defects created by lithium doping may mediate the relative concentration of the intrinsic defects and thereby tune the intrinsic-defect-related visible emission. The enhanced intensity ratio of near-band-edge ultraviolet emission to deep-level visible emission with aging time may be ascribed to both in-diffusion of oxygen from air and self-diffusion of oxygen interstitials to heal the oxygen vacancies during the aging process.  相似文献   

14.
Radiation-defect accumulation and annealing have been examined for nucleardoped silicon in relation to germanium doping level. Results have been obtained from the temperature dependence of the Hall coefficient at various stages in60Co gamma irradiation and subsequent annealing. The formation rates for the main compensating defects (other than A centers) vary nonmonotonically, while the annealing temperatures for carbon-bearing complexes containing E1 levels increase with the germanium concentration. The results are interpreted on the assumption that there are dopant-defect inclusions whose gettering behavior and surrounding stresses are dependent on the germanium level. It is also concluded that there are changes in the effective free-vacancy and interstitial carbon-atom trapping cross sections for oxygen in the presence of germanium.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 98–102, November, 1990.  相似文献   

15.
Sb doped SnO2 (ATO) nanoparticles with Sb doping concentrations ranging from 0% to 20% (Sb/Sb+Sn) have been prepared by chemical coprecipitation using metallic Sn and SbCl3 as raw materials. The influence of Sb doping concentration on crystal structure and electrical property was studied in detail. Results indicated that all ATO nanoparticles possessed the same tetragonal rutile structure as that of bulk SnO2. The average crystal size of the ATO nanoparticles decreased from 16 to 7 nm by increasing the Sb doping concentration. The unit-cell volume of ATO nanoparticles was either expanded or contracted, strongly depending on the Sb doping concentration. The electrical resistivity decreased sharply from 111 to minimum of 1.05 Ω cm when the Sb doping concentration was increased from 0% to 15% and then increased slightly to 1.42 Ω cm when the Sb doping concentration was increased from 15% to 20%. Finally, high resolution X-ray photoelectron spectroscopy (XPS) measurement was employed to investigate the valence state of Sb in samples with various Sb doping levels.  相似文献   

16.
Nano-sized antimony-doped tin oxide (ATO) particles were synthesized using DC arc plasma jet. The precursors SnCl4 and SbCl5 were injected into the plasma flame in the vapor phase. ATO powder could conveniently be synthesized without any other post-treatment in this study. To control the doping amount of antimony in the ATO particles, the Sb/Sn molar ratio was used as an operating variable. To study the effect of carrier gas on the particle size, argon and oxygen gases were used. The results of XRD and TGA show that all Sb ions penetrated the SnO2 lattice to substitute Sn ions. With the increased SbCl5 concentration in source material, the Sb doping level was also increased. The size of the particles synthesized using the argon carrier gas was much smaller than that of the particles prepared using the oxygen carrier gas. For the argon gas, PSA results and SEM images reveal that the average particle size was 19 nm. However, for the oxygen gas, the average particle size was 31 nm.  相似文献   

17.
Sb doped SnO2 films prepared by DC sputtering and heating were characterized by 119Sn conversion electron Mössbauer spectrometry (CEMS). An asymmetric doublet was observed in the Mössbauer spectra of 1 %, 3 %, and 10 % Sb doped SnO2 films. The peak ratios of doublets are considered to be due to the columnar crystal growth on the substrate. With the doping level of Sb, both the isomer shift (δ) and the quadrupole splitting (Δ) increased. After annealing, δ increased and Δ decreased for each sample. These results suggest the followings. The electron doping of the SnO2 lattice by pentavalent Sb induces the increase of the electron density at the SnIV nucleus. The annealing process leads to more complete accommodation of the Sb dopant that results in more effective electron doping and therefore increasing isomer shift for tin. Simultaneously, the distortion of the lattice caused by Sb is relaxed and the quadrupole splitting decreases.  相似文献   

18.
对快速退火后用共蒸发B3方法实现重掺杂硼的硅分子束外延层的电学特性进行了研究.1100℃退火可以使得外延层中载流子浓度提高4倍,空穴的霍耳迁移率与相同浓度下硅体材料的水平相当;外延层与衬底之间载流子浓度转变陡峭,获得了晶体质量良好的外延层. 关键词:  相似文献   

19.
The effects of antimony (Sb) doping on solution‐processed indium oxide (InOx) thin film transistors (TFTs) were examined. The Sb‐doped InSbO TFT exhibited a high mobility, low gate swing, threshold voltage, and high ION/OFF ratio of 4.6 cm2/V s, 0.29 V/decade, 1.9 V, and 3 × 107, respectively. The gate bias and photobias stability of the InSbO TFTs were also improved by Sb doping compared to those of InOx TFTs. This improvement was attributed to the reduction of oxygen‐related defects and/or the existence of the lone‐pair s‐electron of Sb3+ in amorphous InSbO films. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   

20.
通过透射光谱、x射线激发发射光谱(XSL)的测试,研究了Bridgman法生长的几种不同+3价离子掺杂钨酸铅晶体的发光性能,并利用正电子湮没寿命谱(PAT)和x光电子能谱(XPS)的实验手段,对不同钨酸铅晶体的微观缺陷进行研究.实验表明,不同的+3价离子掺杂,对钨酸铅晶体发光性能的改善不同,并使得晶体中正电子俘获中心和低价氧的浓度发生不同变化.其中掺镧晶体的正电子俘获中心和低价氧浓度均上升,而掺钇和掺铋晶体的正电子俘获中心和低价氧浓度均下降,掺锑晶体则出现了正电子俘获中心浓度上升、低价氧浓度下降的情况.提 关键词: 钨酸铅晶体 +3价离子掺杂 正电子湮没寿命谱 x光电子能谱  相似文献   

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