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41.
Crystalline Si thin-film solar cells: a review 总被引:3,自引:0,他引:3
R.B. Bergmann 《Applied Physics A: Materials Science & Processing》1999,69(2):187-194
The present review summarizes the results of research efforts in the field of crystalline silicon thin-film solar cells on
foreign substrates. The large number of competing approaches can be broadly classified according to the grain size of the
crystalline Si films and the doping of the crystalline absorber. Currently, solar cells based on microcrystalline Si films
on glass with an intrinsic or moderately doped absorber film achieve efficiencies around 10%, whereas thin-film cells fabricated
from large-grained polycrystalline Si on high-temperature-resistant substrates have efficiencies in the range of 15%. The
paper discusses the limitations of various approaches and describes recent developments in the area of thin, monocrystalline
Si films that may open the way towards 20% efficient thin-film Si solar cells.
Received: 1 March 1999 / Accepted: 28 March 1999 / Published online: 24 June 1999 相似文献
42.
W. Ebeling H. Hache M. Spahn 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(2):265-272
Applying Gibb's geometrical methods to the thermodynamics of H-plasmas we explore the landscape of the free energy as a function
of the degrees of ionization and dissociation. Several approximations for the free energy are discussed. We show that in the
region of partial ionization/dissociation the quantum Debye-Hückel approximation (QDHA) yields a rather good but still simple
representation which allows to include magnetic field and fluctuation effects. By using relations of Onsager-Landau-type the
probability of fluctuations and ionization/dissociation processes are described. We show that the degrees of ionization/dissociation
are probabilistic quantities which are subject to a relatively large dispersion. Magnetic field effects are studied.
Received 10 September 2002 / Received in final form 26 November 2002 Published online 11 February 2003 相似文献
43.
The resistivity of transparent conducting Al‐ and Ga‐doped ZnO (AZO and GZO) thin films prepared with a thickness in the range from 20 to 200 nm on glass substrates at a temperature below 200 °C was found to increase with exposure time when tested in a high humidity environment (air at 90% relative humidity and 60 °C). The resistivity stability (resistivity increase) was considerably affected by the thin film thickness. In particular, thin films with a thickness below about 50 nm were very unstable. The increase in resistivity is interpreted as carrier transport being dominated by grain boundary scattering resulting from the trapping of free electrons due to oxygen adsorption on the grain boundary surface. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
44.
Diane Maclagan 《Proceedings of the American Mathematical Society》2001,129(6):1609-1615
The main result of this paper is that all antichains are finite in the poset of monomial ideals in a polynomial ring, ordered by inclusion. We present several corollaries of this result, both simpler proofs of results already in the literature and new results. One natural generalization to more abstract posets is shown to be false.
45.
T. Sameshima Y. Kaneko N. Andoh 《Applied Physics A: Materials Science & Processing》2001,73(4):419-423
50-nm thick amorphous silicon films formed on glass substrates were crystallized by rapid Joule heating induced by an electrical
current flowing in 100-nm-thick Cr strips formed adjacently to 200-nm-thick SiO2 intermediate layers. 3-μs-pulsed voltages were applied to the Cr strips. Melting of the Cr strips caused a high Joule heating
intensity of about 1×106 W/cm2. Raman scattering measurements revealed complete crystallization of the silicon films at a Joule heating energy of 1.9 J/cm2 via the SiO2 intermediate layer. Transmission electron microscopy measurements confirmed a crystalline grain size of 50–100 nm. 1-μm-long
crystalline grain growth was also observed just beneath the edge of the Cr strips. The electrical conductivity increased from
10-5 S/cm to 0.3 S/cm for 7×1017-cm-3-phosphorus-doped silicon films because of activation of the phosphorus atoms because of crystallization. The numerical analysis
showed a density of localized defect states at the mid gap of 8.0×1017 cm-3. Oxygen plasma treatment at 250 °C and 100 W for 5 min reduced the density of the defect states to 2.7×1017 cm-3.
Received: 3 April 2001 / Accepted: 9 April 2001 / Published online: 25 July 2001 相似文献
46.
Polynomial interpolation in several variables 总被引:10,自引:0,他引:10
This is a survey of the main results on multivariate polynomial interpolation in the last twenty-five years, a period of time
when the subject experienced its most rapid development. The problem is considered from two different points of view: the
construction of data points which allow unique interpolation for given interpolation spaces as well as the converse. In addition,
one section is devoted to error formulas and another to connections with computer algebra. An extensive list of references
is also included.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
47.
黄心中 《数学年刊A辑(中文版)》2014,35(4):413-422
研究平面拟共形映照的偏差函数μ(r),λ(K)和ηK(t).利用环形区域模函数的共形不变性,证明μ(r)满足一个新的不等式.作为应用,不必利用椭圆函数的性质,得到了估计Gr(o|¨)tzsch,Teichm(u|¨)ller和Mori这3种典型极值环形区域模函数的更精确的不等式,并得到了λ(K)和ηK(t)的更精确的上下界估计不等式.改进了由Anderson,Vamanamurthy,Qiu和Vuorinen所得的相应结果. 相似文献
48.
证明了半序线性空间上线性泛函的两个Gr\"{u}ss型不等式, 并由此给出了Karamata型积分不等式的一种推广形式,
得到了一个新的Gr\"{u}ss型积分不等式及关于傅立叶系数的两个不等式.
最后利用所得结论研究了关于矩阵及线性算子的一些Gr\"{u}ss型不等式. 相似文献
49.
P. Kounavis 《Solid State Communications》2004,131(1):47-51
The density of the trapping centers and their capture radius for holes in a-As2Se3 are determined by analyzing the imaginary term of the modulated photocurrent. The light-induced changes in the imaginary term are also examined to study the influences of the photo structural changes to the density of states and to detect possible hole trapping at light created charged defects. 相似文献
50.
The surface effects, the (NH4)2S and low-temperature-deposited SiNx passivations of InP-based heterostructure bipolar transistors (HBTs) have been investigated. The surface recombination current of InP-based HBTs is related to the base structures. The (NH4)2S treatment for InGaAs and InP removes the natural oxide layer and results in sulfur-bonded surfaces. This can create surface-recombination-free InP-based HBTs. Degradation is found when the HBTs were exposed to air for 10 days. The low-temperature-deposited SiNx passivation of InGaAs/InP HBTs causes a drastic decrease in the base current and a significant increase in the current gain. The improvement in the HBT performance is attributed to the low deposition temperature and the effect of N2 plasma treatment in the initial deposition process. The SiNx passivation is found to be stable. S/SiNx passivation of InGaAs/InP HBTs results in a decrease in the base current and an increase in the current gain. The annealing process can cause the base current to decrease further and the current gain increase. 相似文献