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1.
The electron mobility for strained Si1-xGex alloy layer grown on Si(100) substrate has been calculated for doping rage of 10^17 cm^-3 to 10^20 cm^-3with Ge contents of 0.0≤x≤1.0.The results show a decrease in the mobility with increasing of Ge content and doping concentration.The electron mobility in-plane is foud to be smaller than the perpendicular component. 相似文献
2.
The effect of the annealing time and annealing temperature on Ni/Ge/Au electrode contacts deposited on the n-type InP contact layer has been studied using a circular transmission line model. The minimum specific contact resistance of 3.210 7 cm2was achieved on the low-doped n-type InP contact layer with a 40 s anneal at 425 ℃. In order to improve the ohmic contact and reduce the difficulty in the fabrication of the high doped InP epi-layer, the doping concentration in the InP contact layer was chosen to be 51018cm 3in the fabrication of transferred electronic devices. Excellent differential negative resistance properties were obtained by an electron beam evaporating the Ni/Ge/Au/Ge/Ni/Au composite electrode on an InP epi-layer with a 60 s anneal at 380 ℃. 相似文献
3.
In this report,the interdiffusion between the p-InP with Au-Zn,Ti/Au,Pd/Au and Ti/Pd/Au at interface have been investigated by Auger electron spectroscopy and electron spectroscopy for chemical analysis.The surface morphology for the heat treatment are observed with scanning electron microscopy. It is found that the indiffusion of Au is easier than that of Pd and Ti and the outdiffusion of In is easier than that of P.The combination state of In and Au is formed during the heat treatment of p-InP/Au-Zn. The effects of the alloying temperature and time on the specific contacts resistance of p-InP/Au-Zn system are studided.The low specific contact resistance,p_c=2.4-2.7×10~(-4)Ω-cm~2,is obtained when alloying at 450℃ for 2 min or at 350℃ for 30 min. These results indicate that the specific contact resistance strongly depend on the“interdiffusion degree”.The Zn in Au-Zn ahoy distributes onto the most surface layer of p-InP/Au-Zn system during evaporation process and heat treatment.It may be one of the reasons for the higher specific contacts resistance. 相似文献
4.
The multi-layer metals of Ni/Au Ge/Pt/Au with a Pt diffusion barrier layer of ohmic contact to n-GaAs were studied. The surface morphology and ohmic contact resistivity of multi-layer metals were characterized, with and without the Pt diffusion barrier layer for comparison. The SEM and EDS measurements show the Pt diffusion barrier layer can block the interdiffusion of atoms in multi-layer metals, and improve the surface morphology.The TLM results show that the samples with a Pt diffusion barrier layer have uniform ohmic contact resistance,indicating that the Pt diffusion barrier layer can increase the repetition and uniformity of ohmic contact to n-GaAs,and improve the thermal stability and reliability of GaAs-based devices. 相似文献
5.
LI Chao ZHOU Xun ZOU Ze-ya DU Jiang-feng JI Hong State key Laboratory of Electronic Thin Films Integrated Devices University of Electronic Science Technology of China Chengdu CHN YANG Mo-hua ZHAO HongChongqing Optoelectronics Research Institute Chongqing CHN ZHAO Jin-xia ZHU Yan-ling YU Zhi-wei YU Qi 《半导体光子学与技术》2008,14(2):80-84
The residual strain and the damage induced by Si implantation in GaN samples have been studied, as well as the electronic characteristics. These as-grown samples are implanted with different doses of Si(1 × 10^14 cm^-2, 1×10^15 cm^-2 or ] × 10^16 cm^-2, ]00 keV) and following annealed by rapid thermal anneal(RTA) at 1 000℃ or 1 100℃ for 60 s. High resolution X-ray diffractometer(HRXRD) measurement reveals that the damage peak induced by the implantation appears and increases with the rise of the impurity dose, expanding the crystal lattice. The absolute value of biaxial strain decreases with the increase of the annealing temperature for the same sample. RT-Hall test reveals that the sample annealed at 1 100℃ acquires higher mobility and higher carrier density than that annealed at 1 000 ℃, which reflects that the residual strain(or residual stress) is the main scattering factor. And the sample C3(1 × 10^16 cm^-2 and annealed at 1100 ℃) acquires the best electronic characteristic with the carrier density of 3.25 × 10^19 cm^-3 and the carrier mobility of 31 cm2/(V·S). 相似文献
6.
In this report,the interdiffusion between the p-InP with Au-Zn,Ti/Au,Pd/Au and Ti/Pd/Au atinterface have been investigated by Auger electron spectroscopy and electron spectroscopy for chemicalanalysis.The surface morphology for the heat treatment are observed with scanning electron microscopy.It is found that the indiffusion of Au is easier than that of Pd and Ti and the outdiffusion of In is easierthan that of P.The combination state of In and Au is formed during the heat treatment of p-InP/Au-Zn.The effects of the alloying temperature and time on the specific contacts resistance of p-InP/Au-Zn systemare studided.The low specific contact resistance,p_c=2.4-2.7×10~(-4)Ω-cm~2,is obtained when alloying at450℃ for 2 min or at 350℃ for 30 min.These results indicate that the specific contact resistance strongly depend on the“interdiffusiondegree”.The Zn in Au-Zn ahoy distributes onto the most surface layer of p-InP/Au-Zn system duringevaporation process and heat treatment.It may be one of the reasons for the higher specific contactsresistance. 相似文献
7.
The defects in lnGaAsP/InP DH LEDs are observed with an infrared line scanner.The dark structure appears before aging and it exists mainly in the form of dark spot defect.The effect of the variety and concentration of the doping for p-InP confining layers on the dark defects is studied.The results show that the percentage of devices with dark defects is much lower for Mg or In-Zn doped devices than for Zn doped devices.It is believed that Zn is one of the important origin for the formation of dark defects.The growth rate of dark defects is studied both at room temperature and at 70—85℃.The results show that after agin for 15000 h at room temperature there are no dark defects newly appeared.But after aging for 2000 h at 70—85℃ some devices show newly formed dark structure with very slow growth rate. 相似文献
8.
The Ni/Au contact was treated with oxalic acid after annealing in 02 ambient, and its 1-V characteristic showed the property of contact has been obviously improved. An Auger electron spectroscopy (AES) depth profile of the contact as-annealed showed that the top layer was highly resistive NiO, while an X-ray photo-electron spectroscopy (XPS) of oxalic acid treated samples indicated that the NiO has been removed effectively. A scanning electron microscope (SEM) was used to observe the surface morphology of the contacts, and it was found that the lacunaris surface right after annealing became quite smooth with lots of small Au exposed areas after oxalic acid treatment. When the test probe or the subsequently deposited Ti/Au was directly in contact with these small Au areas, they worked as low resistive current paths and thus decrease the specific contact resistance. 相似文献
9.
The stresses, structural and electrical properties of n-type Si-doped GaN films grown by metaiorganic chemical vapor deposition (MOCVD) are systemically studied. It is suggested that the main stress relaxation is induced by bending dislocations in low doping samples. But for higher doping samples, as the Si doping concentration increases, the in-plane stresses in the grown films are quickly relaxed due to the rapid increase of the edge dislocation densities. Hall effect measurements reveal that the carrier mobility first increases rapidly and then decreases with increasing Si doping concentration. This phenomenon is attributed to the interaction between various scattering process. It is suggested that the dominant scattering process is defect scattering for low doping samples and ionized impurity scattering for high doping samples. 相似文献
10.
Fe-doped ZnO thin films have been prepared by spray pyrolysis on glass substrates and the influence of Fe-doping concentration on the structural and optical properties of the films has been studied.The X-ray diffraction (XRD) analysis shows that Fe doping has a significant effect on crystalline quality,grain size and strain in the thin films.The best crystalline structure is obtained for 3 at%Fe doping as observed from scanning electron microscopy (SEM) and XRD.However,lower or higher Fe-doping degrades the crystalline quality in turn.Moreover,UV spectroscopy demonstrates the influence of Fe-incorporation on visible range transmittance of ZnO where the best transmittance is obtained for 3 at%doping.The results have been illustrated simultaneously focusing previous results obtained from literature. 相似文献
11.
本文基于费米黄金法则和波尔兹曼碰撞项近似理论,对Si基应变材料各空穴散射机率与应力强度、晶向的关系进行了深入的研究。结果表明:1)在应力的作用下,Si基应变材料总散射几率明显降低;2)当Ge组分为0.2时,总散射几率量化排序为应变Si/(111)Si1-xGex>应变Si/(101)Si1-xGex>应变Si1-xGex/(111)Si>应变Si1-xGex/(101)Si>应变Si/(001)Si1-xGex>应变Si1-xGex/(001)Si;3)应力作用下空穴声学声子散射几率的降低是引起Si基应变材料总散射几率降低的主要原因。本文量化结论可为Si基应变及其他应变材料的相关研究提供重要理论参考。 相似文献
12.
Ming-Shaw Chung Ming-Jun Wang Wen-Tai Lin T. C. Chang Y. K. Fang 《Journal of Electronic Materials》2002,31(5):500-505
Interfacial reactions and electrical properties of Hf/p-Si0.85Ge0.15 as a function of the annealing temperature were studied. Hf3(Si1−xGe)2 and Hf(Si1−xGe)2 were initially formed at 500°C and 600°C, respectively. At temperatures above 400°C, Ge segregation out of the reacted layers
associated with strain relaxation of the unreacted Si0.85Ge0.15 films appeared. At 780°C, agglomeration occurred in the Hf(Si1−xGex)2 films. All the as-deposited and annealed Hf/p-Si0.85Ge0.15 samples showed the formation of an ohmic contact. The lowest specific contact resistance around 10−5 ω cm2 could be obtained for the Hf3 (Si1−xGex)2 contacts to p-Si0.85Ge0.15 formed at 500°C. Below 500°C, the decrease of specific contact resistance with the annealing temperature is mainly caused
by the formation of Hf3(Si1−xGex)2 and an interfacial Ge-rich layer between the Hf3(Si1−xGex)2 and unreacted Si0.85Ge0.15 films, while above 600°C, the increase of specific contact resistance may be due to the formation of Hf(Si1−xGex)2 and SiC as well as the roughness of the Hf(Si1−xGex)2 films. 相似文献
13.
Y. Miron M. Efrati Fastow C. Cytermann R. Brener M. Eizenberg M. Glück H. Kibbel U. Knig 《Materials Science in Semiconductor Processing》1998,1(3-4)
The reaction of cobalt with the Si-sacrificial cap in the strained Si/Si1−xGex/Si MBE grown heterostructure was studied. The Si-cap is added to prevent the relaxation of the SiGe and to guarantee uniform and reliable silicidation reaction. The Si1−xGex epilayer, with Ge content between 18 and 28 at%, was highly B doped, while the Si-cap was undoped or B doped either during growth or by ion implantation. Cobalt evaporation was followed by rapid thermal annealing at 450–700°C for 30 sec in N2 or Ar+10%H2. When the silicide penetrated the Si-cap/Si1−xGex interface, noticeable out-diffusion of Ge and B to the surface was observed. In spite of the presence of the Si-cap significant strain relaxation was observed in three cases: (1) in the implanted samples, although the implantation was confined to the Si-cap, (2) when the Co layer was too thick, such that the silicide penetrated the SiGe layer and (3) when the Ge content in the SiGe layer was relatively high (27.5%). 相似文献
14.
《Solid-state electronics》1987,30(3):339-343
The I-V characteristics of aluminum Schottky diodes made on LPCVD deposited polysilicon with a wide range of doping concentration (8.5 × 1015−1.7 × 1020 cm−3) have been investigated. Diodes with ideality factor n = 1.12 at room temperature were obtained with doping concentration ≤ 8.5 × 1016 cm−3. In contrast to large grain polysilicon, uniform I-V characteristics can be obtained across the wafer on fine grain LPCVD polysilicon. A barrier height of qφB0.73 eV at 300 K was consistently determined from both the I-V measurements and the specific contact resistance measurements. The contact resistance of aluminum/polysilicon contacts is well described by present theory except in the intermediate doping range. 相似文献
15.
Haijun Jia Takuya Matsui Michio Kondo 《Progress in Photovoltaics: Research and Applications》2012,20(1):111-116
Ga doped ZnO (GZO) films prepared by sputtering at room temperature were rapid thermal annealed (RTA) at elevated temperatures. With increasing annealing temperature up to 570°C, film transmission enhanced significantly over wide spectral range especially in infrared region. Hall effect measurements revealed that carrier density decreased from ∼8 × 1020 to ∼ 3 × 1020 cm−3 while carrier mobility increased from ∼15 to ∼28 cm2/Vs after the annealing, and consequently low film resistivity was preserved. Hydrogenated microcrystalline Si (µc‐Si:H) and microcrystalline Si1‐xGex (µc‐Si1‐xGex:H, x = 0.1) thin film solar cells fabricated on textured RTA‐treated GZO substrates demonstrated strong enhancement in short‐circuit current density due to improved spectral response, exhibiting quite high conversion efficiencies of 9.5% and 8.2% for µc‐Si:H and µc‐Si0.9Ge0.1:H solar cells, respectively. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
16.
Silicon (Si) and Si with a 60 nm Si0.95Ge0.05 epilayer cap (Si0.95Ge0.05/Si) were implanted with 60 keV, 1×1013 cm−2 boron (B) followed by annealing in nitrogen (N2) or dry oxygen (O2) in two different anneal conditions. B+implantation energy and dose were set such that the B peak is placed inside Si in Si0.95Ge0.05/Si samples and concentration independent B diffusion is achieved upon annealing. For samples annealed above 1075 °C, Ge diffusing from the Si0.95Ge0.05 epilayer cap in Si0.95Ge0.05/Si samples reached the B layer inside Si and resulted in retarded B diffusion compared to the Si samples. For annealing done at lower temperatures, diffusion of Ge from Si0.95Ge0.05 epilayer cap does not reach the B layer inside Si. Thus B diffusion profiles in the Si and Si0.95Ge0.05/Si samples appear to be similar. B diffusion in dry oxidizing ambient annealing of Si0.95Ge0.05/Si samples further depends on the nature of Si0.95Ge0.05 oxidation which is set by the duration and the thermal budget of the oxidizing anneal. 相似文献
17.
Hall effect and resistivity measurements on Be implanted GaAs1-xPx(x~0.38) indicate that essentially 100% doping efficiency may be obtained for normal Be concentrations after a 900°C anneal using either SiO2 or Si3N4 as an encapsulant. The temperature dependence of hole mobility in these samples exhibits impurity banding effects similar to those reported in heavily Zn doped GaAs. Hall effect measurements in conjunction with successive thin layer removal techniques indicate there is no significant diffusion of the implanted Be during anneal for a fluence of 6×1013 ions/cm2. 相似文献
18.
A. I. Veinger A. G. Zabrodski T. V. Tisnek S. I. Goloshchapov N. V. Abrosimov 《Semiconductors》2007,41(6):666-672
The electron spin resonance (ESR) at phosphorus dopants in the P-doped Si1−x
Ge
x
alloys (0 < x < 0.057) with the concentration of phosphorus in the range 1015–1016 cm−3 is studied at temperatures from 3 to 30 K. The ESR spectra of the alloys (x > 0) are compared to the ESR spectra of similar silicon samples (x = 0). It is found that, from the smallest Ge content x = 0.008, the ESR spectra contain two additional lines. It is assumed that these lines are due to phosphorus dopants located
in clusters with higher Ge content. It is found that an increase in the Ge content in the alloys up to x = 0.024 yields only an increase in the concentration of such clusters. At x ≥ 0.024, the Ge content increases with x both inside and outside the clusters.
Original Russian Text ? A.I. Veinger, A.G. Zabrodskiĭ, T.V. Tisnek, S.I. Goloshchapov, N.V. Abrosimov, 2007, published in
Fizika i Tekhnika Poluprovodnikov, 2007, Vol. 41, No. 6, pp. 687–693. 相似文献
19.
随着硅浓度的增大,计算的拉曼谱结果表明,Ge-Si模式和Si-Si模式向高波数移动,而Ge-Ge模式向低波数移动,这种拉曼谱的变化强烈的依赖于合金微结构的变化。它的模式频率的线性变化依赖于Ge/Si的力学常熟的变化。这种现象可以用来鉴别合金中Si含量的浓度。可以通过拉曼散射表征这种复杂的微结构变化。 相似文献
20.
D. Y. C. Lie A. Vantomme F. Eisen T. Vreeland M. -A. Nicolet T. K. Carns K. L. Wang B. Holländer 《Journal of Electronic Materials》1994,23(4):369-373
We compare both the strain and damage that 100 keV Si irradiation at room temperature introduces in pseudomorphic and relaxed
GexSi1−x films grown on Si(100) substrates. The ion range is such that the Si/GexSi1−x interface is not significantly damaged. The amount of damage produced in pseudomorphic and relaxed GexSi1−x layers of similar x for irradiation doses up to 2.5 × 1014 Si/cm2 is the same, which proves that a pre-existing uniform strain does not noticeably affect the irradiation-induced damage. However,
the irradiation-induced strain does depend on the pre-existing strain of the samples. Possible interpretations are discussed.
On leave from Inst. voor Kern en Stralingsfysika, Catholic University of Leuven, Belgium. 相似文献