共查询到19条相似文献,搜索用时 171 毫秒
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利用脉冲激光沉积技术在掺Nb的SrTiO3衬底上制备了氧非正分La0.9Ba0.1MnO3-δ/SrTiO3:Nb p-n异质结.在20—300K这一较宽的温度范围内获得了光滑的整流曲线.整流实验表明:该p-n异质结的正向扩散电压VD随着温度升高在薄膜金属—绝缘转变温度附近出现极大值,表现出与氧正分La0.9Ba0.
关键词:
0.9Ba0.1MnO3-δ薄膜')" href="#">La0.9Ba0.1MnO3-δ薄膜
锰氧化物p-n结
整流性质 相似文献
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以单质硼和高纯石墨的混合粉末压制成型的靶材作为靶源,采用过滤阴极真空电弧技术制备不同硼含量的掺硼四面体非晶碳膜.分别采用四探针法、阻抗分析仪和电化学界面对薄膜的变温电导率、I-V特性和C-V特性进行了测试和研究.实验结果表明,当B含量由0增加至6.04 at%时,薄膜的室温电导率先逐渐增大而后逐渐减小,相应薄膜的电导激活能先逐渐减小而后逐渐增大,并在2.13 at%时分别出现最大和最小值1.42×10-7S/cm和0.1eV.此外,掺硼四面体非晶碳/n型硅异质结的I-V曲线表现出典型的整流特性,表明p-n结二极管已经形成,且结两端的掺杂能级在空间上连续统一.
关键词:
四面体非晶碳
电导率
I-V曲线')" href="#">I-V曲线
C-V曲线')" href="#">C-V曲线 相似文献
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分别对带隙较宽(较窄)的p型材料在带隙较窄(较宽)的n型材料之上的碲镉汞(MCT)异质结的能带结构进行了理论分析.在应用的理论模型中提出了一个简单的载流子浓度近似模型用于计入载流子简并效应和导带非抛物线性,同时还考虑到了价带失配的影响.就p-n结位置(zB)和界面电荷密度(Q)两个参数对MCT异质结能带结构的影响进行了系统分析,发现这些影响是不可忽略的.根据这些影响特征,进一步得出了zB和Q参数之间的优化设计规律.
关键词:
碲镉汞(MCT)
异质结
载流子浓度近似 相似文献
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本文系统研究了氧离子注入剂量和退火温度对含有Si-V发光中 心的微晶金刚石薄膜的微结构和光电性能的影响. 结果表明, 氧离子注入并在较高温度退火有利于提高薄膜中Si-V中心的发光强度. 当氧离子注入剂量从1014 cm-2增加到1015 cm-2时, 薄膜中Si-V发光强度增强. Hall效应测试结果表明退火后薄膜的面电阻率降低. 不同温度退火时, 氧离子注入薄膜的Si-V发光强度较强时, 薄膜的面电阻率增加, 说明Si-V发光中心不利于提高薄膜的导电性能. Raman光谱测试结果表明, 薄膜中缺陷数量的增多会增强Si-V的发光强度, 而降低薄膜的导电性能.
关键词:
金刚石薄膜
氧离子注入
电学性能
Si-V缺陷 相似文献
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利用直流磁控溅射技术在玻璃衬底上沉积了TiO2薄膜,并对其进行了Co离子注入,最后在真空中500 ℃退火50 min,得到系列薄膜样品. 利用剥离-分散方法制备了薄膜的透射电镜样品,并用扫描电镜(SEM)、X射线能量散射谱(EDX)和高分辨透射电镜(HRTEM)对样品做了近似原位观察,研究了薄膜样品中不同Co离子注入深度的成分分布和显微结构. 结果表明,薄膜呈锐钛矿结构,Co元素主要分布在薄膜表层,Co离子的注入使TiO2薄膜的晶粒被部分破坏,并形成CoO,而5
关键词:
2薄膜')" href="#">Co注入TiO2薄膜
电镜原位观察
室温铁磁性 相似文献
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A simple technique for the study of the spatial distribution of the damage produced by ion implantation of silicon has been developed. The damage depth distribution for 40 keV boron ions in silicon has been studied at irradiation doses from 7 × 1011 to 3.9 × 1014 ions/cm2 and the relative defect peak depth R d/R p = 0.85 determined. An increase of layer conductivity as the surface part of the implanted layer is removed has been revealed. This effect is caused by the presence of radiation defects in the surface region of the layer. The “electrical” cluster diameter is about 28 A and the overlapping cluster dose is close to 1 × 1013 ions/cm2. 相似文献
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A. Rogalski J. Rutkowski K. Jóźwikowski J. Piotrowski Z. Nowak 《Applied Physics A: Materials Science & Processing》1990,50(4):379-384
This paper considers the Hg1–x
Zn
x
Te alloy system as a potential material for the fabrication of infrared photodiodes. The influence of different junction current components (diffusion, tunneling and depletion layer currents) on the R
0
A product of n+-pHg1–x
Zn
x
Te photodiodes is analysed. The upper theoretical limits of the R
0
A product and detectivity are determined. Results of calculations are compared with experimental data reported by other authors and those measured in our laboratory. Preliminary results on related technology and the properties of Hg1–x
Zn
x
Te prepared by the ion-etching technique are presented. 相似文献
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V.V. Vasilyev A.V. Predein V.S. Varavin N.N. Mikhailov S.A. Dvoretsky J.V. Gumenjuk-Sichevska A.G. Golenkov V.P. Reva I.V. Sabinina Yu.G. Sidorov A.O. Susliakov F.F. Sizov A.L Aseev 《Opto-Electronics Review》2010,18(3):332-337
The long wavelength (8–12 μm) IR FPA 288×4 based on a hybrid assembly of n+-p diode photosensitive arrays (PA) of HgCdTe (MCT) MBE-grown structures and time delay integration (TDI) readout integrated circuits (ROIC) with bidirectional scanning have been developed, fabricated, and investigated. The p-type MCT structures were obtained by thermal annealing of as-grown n-type material in inert atmosphere. The MCT photosensitive layer with the composition 0.20–0.23 of mole fraction of CdTe was surrounded by the wide gap layers to decrease the recombination rate and surface leakage current. The diode arrays were fabricated by planar implantation of boron ions into p-MCT. The typical dark currents were about 4–7 nA at the reverse bias voltage of 150 mV. The differential resistance R was up to R0 = 1.6×107 Ω zero bias voltage, which corresponded to R0A ~70 Ω ·cm2 and to the maximal value Rmax = 2.1 × 108 Ω. The bidirectional TDI deselecting ROIC was developed and fabricated by 1.0-μm CMOS technology with two metallic and two polysilicon layers. The IR FPAs were free of defect channels and have the average values of responsivity Sλ = 2.27×108 V/W, the detectivity Dλ * = 2.13 × 1011 cm × Hz1/2 × Wt1, and the noise equivalent temperature difference NETD = 9 mK. 相似文献
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J. Rutkowski P. Madejczyk A. Piotrowski W. Gawron K. Jóźwikowski A. Rogalski 《Opto-Electronics Review》2008,16(3):321-327
The performance of dual waveband HgCdTe photodiodes fabricated using metaloorganic chemical vapour deposition operated at
high temperatures is presented. The effect of additional separating layer on the quantum efficiency and cross-talk of the
photodiodes is analyzed. The photodiodes with cutoff wavelengths up to 6 μm, good R0A product, and high quantum efficiency at 200 K have been demonstrated. The temperature dependence of the differential resistance
is discussed. It is shown that the multilayer heterojunction P-n-N-n-P structure operating in a simultaneous mode has better
performance than a structure operating in a sequential mode. 相似文献
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21.0%‐efficient co‐diffused screen printed n‐type silicon solar cell with rear‐side boron emitter 下载免费PDF全文
Nadine Wehmeier Bianca Lim Anja Nowack Jan Schmidt Thorsten Dullweber Rolf Brendel 《固体物理学:研究快报》2016,10(2):148-152
Plasma enhanced chemical vapor deposition (PECVD) is applied to deposit boron silicate glasses (BSG) acting as boron diffusion source during the fabrication of n‐type silicon solar cells. We characterize the resulting boron‐diffused emitter after boron drive‐in from PECVD BSG by measuring the sheet resistances Rsheet,B and saturation current densities J0,B. For process optimization, we vary the PECVD deposition parameters such as the gas flows of the precursor gases silane and diborane and the PECVD BSG layer thickness. We find an optimum gas flow ratio of SiH4/B2H6= 8% and layer thickness of 40 nm. After boron drive in from these PECVD BSG diffusion sources, a low J0,B values of 21 fA/cm2 is reached for Rsheet,B = 70 Ω/□. The optimized PECVD BSG layers together with a co‐diffusion process are implemented into the fabrication process of passivated emitter and rear totally diffused (PERT) back junction (BJ) cells on n‐type silicon. An independently confirmed energy conversion efficiency of 21.0% is achieved on 15.6 × 15.6 cm2 cell area with a simplified process flow. This is the highest efficiency reported for a co‐diffused n‐type PERT BJ cell using PECVD BSG as diffusion source. A loss analysis shows a small contribution of 0.13 mW/cm2 of the boron diffusion to the recombination loss proving the high quality of this diffusion source. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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In the system of boron and carbon, the formation of boron carbide was investigated after ion implantation of 25 keV B ions into carbon or of 25 keV C ions into boron and subsequent annealing. TEM and electron diffraction studies showed that the crystallization of boron carbide begins only at temperatures above 1050°C. By implantation of 20 keV C ions into iron (ion dose 1017 C ions/cm2) only the metastable ε-Fe2O will be generated, which at above 220°C transforms into the stable cementite Fe3C. After implantation of 20 keV B ions into iron, no formation of iron boride could be found. These experimental facts can be understood qualitatively with the help of the thermal-spike model. The energy density or the temperature in the thermal spikes is not sufficient for the generation of cementite iron boride or boron carbide. 相似文献
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We considered the factors due to which the dependences between the uranium–oxygen distances R
0 and the frequencies of valence vibrations as for complex compounds of uranyl are described by two independent expressions generally represented by equations of the type R
0 = a + bas
–2/3 (b > 0) with the coefficients a and b differing in the regions R
0 < 0.178 nm and R
0 > 0.178 nm. It is shown that the reason is that there is a mutual effect of the ligands in the uranyl complex responsible for different partial contributions of the uranium orbitals and of the atoms of the first coordination sphere to the chemical bonding. 相似文献
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Richard A. Brandt 《Nuclear Physics B》1974,83(1):60-92
If the appropriate high-energy limits of the amplitudes are Regge pole dominated, then the large distance (x0 → ∞, x2fixed) behavior of the current product is completely characterized by an operator expression , involving only local operators at 0, which is such that and W have the same high-energy behavior. In the only case (|b> a single particle stateand |b′> the vacuum) where W is not Regge behaved, it is shown that R is identical to W, and so the relation is established as a large distance operator expansion, valid between all states. is expressed as a differential operation B(□x, ?x · ?0, □0) on the light-cone expansion and some of its properties are deduced by carrying out the differentiations. A second form of is given in terms of non-local “reggeon” field operators Rαm(0) (α is a (fixed) spin index and m is a (variable) helicity index) which might be useful coordinate in reggeon field theories. These operators can be used to define reggeon-particle amplitudes and if conventional double-Regge and triple-Regge behaviors are further assumed, the large distance behaviors of the current-reggeon and reggeon-reggeon field products are specified in terms of other reggeon fields. 相似文献