共查询到20条相似文献,搜索用时 15 毫秒
1.
E. V. Astrova N. E. Preobrazhenskiy S. I. Pavlov V. B. Voronkov 《Semiconductors》2017,51(9):1153-1163
Interest in the sintering of macroporous silicon is due to the possibility of purposefully modifying its structure. The annealing of macroporous structures in an atmosphere of Ar, instead of H2, simplifies the requirements to equipment and safety engineering. The sintering of macroporous silicon as result of annealing at T = 1000–1280°C in a horizontal tube purged with high-purity gases: Ar or Ar + 3%H2 is examined. Experiments were conducted with layers having deep cylindrical macropores produced by the electrochemical etching of samples with seed pits on their surface (ordered pores) and without seeds (random pores). The morphology of the porous structure and the changes in this structure upon annealing are studied with electron and optical microscopes. It is shown that, depending on the pore diameter and treatment temperature, the following transformation occurs: the pore surface is smoothed, pores are closed and a surface crust is formed, cylindrical pores are spheroidized and decompose into isolated hollow spheres, and a fine structure and faceting are formed. It is shown that the (111) planes have the minimal surface energy. It is found that the annealing of macroporous silicon in an inert gas leads to strong thermal etching, which is manifested in the fact that the porosity increases or even the porous layer at the sample edge fully disappears. Moreover, an oxide layer appears as a film, beads, or long filaments forming a glass wool upon annealing, especially at low temperatures. These features can be attributed to the presence of trace amounts of an oxidizing agent in the inert gas, which causes the formation of highly volatile SiO and products formed in the reaction involving this compound. 相似文献
2.
A. A. Nechitaĭlov E. V. Astrova Yu. A. Kukushkina S. Yu. Kameneva 《Semiconductors》2006,40(10):1222-1226
A simple nondestructive method to find the internal surface area, porosity, pore diameter, and pore density in macroporous silicon with through channels is suggested and tested. The porosity p is determined from the mass loss upon anodizing, and the surface area per unit volume, S v , from the mass of SiO2 formed on the pore surface upon thermal oxidation. The relations are given for calculation of the average pore diameter d and pore density N from the obtained S v and p. Dependences of the specific surface area and porosity on the resistivity of initial n-Si in the range ρ = 3–25 Θ cm have been studied for samples with ordered and self-organized “lattices” of macropores. The obtained values are within the limits p = 27–50%, S v = 2800–6000 cm2/cm3, d = 1.9–6.5 μm, and N = 1.4?10 × 106 cm?2, in agreement with the data fumished by microscopy. 相似文献
3.
E. V. Ivanova A. A. Sitnikova O. V. Aleksandrov M. V. Zamoryanskaya 《Semiconductors》2016,50(6):791-794
It is found for the first time that silicon nanoclusters are formed in the surface layer of thermal silicon dioxide under high-temperature annealing (T = 1150°C) in dried nitrogen. Analysis of the cathodoluminescence spectra shows that an imperfect surface layer appears upon such annealing of silicon dioxide, with silicon nanoclusters formed in this layer upon prolonged annealing. Transmission electron microscopy demonstrated that the silicon clusters are 3–5.5 nm in size and lie at a depth of about 10 nm from the surface. Silicon from the thermal film of silicon dioxide serves as the material from which the silicon nanoclusters are formed. This method of silicon-nanocluster formation is suggested for the first time. 相似文献
4.
In the work some peculiarities in formation of the porous silicon, its morphology and composition were investigated, as well as some optical properties of this material. Porous silicon was obtained on the substrates of single-crystalline Si as well as on the silicon structures with p–n junctions. In order to obtain nano-, meso- and macroporous silicon as well as multi-layered porous structures several technological parameters (were controlled) varied—orientation of the substrates, conductivity type and composition of the etchant. Correlation between photoluminescence intensity of the obtained samples and intensity of the absorption band in their IR spectra (the band at 616 cm−1) that is due to the presence of Si–Si bonds in porous layer was observed. The influence of the porous silicon storage in the air on the degradation of its photoluminescence parameters was also estimated. 相似文献
5.
Optical transmission spectra of macroporous silicon with through pores has been studied experimentally and theoretically in
the spectral range 0.3–0.8 μm (in which single-crystal Si is opaque). The spectra are discussed in terms of the general diffraction
theory. Expressions taking into account the diffraction at the entrance and exit of pores and the influence exerted by deviation
of the angle of light incidence from the normal are derived. The transmission spectrum is fairly well described by the results
of calculation.
__________
Translated from Fizika i Tekhnika Poluprovodnikov, Vol. 37, No. 1, 2003, pp. 57–64.
Original Russian Text Copyright ? 2003 by Astrova, Korovin, Lang, Remenyuk, Shuman. 相似文献
6.
为了研究硅振荡器的特性,本文采用硅振荡器和传统石英晶振的对比实验来研究,通过对石英晶振的特性比较全面的把握,利用石英晶振的频率值精度高、温漂小、抖动不明显的特征,来研究硅振荡器的实际频率值、温漂和抖动特性,所采用的方法是使用鉴相器的频率合成方法来比对得出硅振荡器的特性参数,其中选用MAX7375硅振荡器和KSS石英晶振通过温度的变化以及抖动的测试完成硅振荡器的初步特性分析,方便为后期使用硅振荡器来校准晶振做基础性研究。 相似文献
7.
The deformation behavior of a macroporous silicon wafer subjected to high-temperature oxidation has been studied, and the basic parameters describing the sample bending and subsequent stress relaxation when oxide is removed are determined. X-ray diffractometry and topography were used to determine the sample bending radius and lattice parameters, and to reveal the areas of dislocation generation. The strain of a silicon lattice in oxidized macroporous Si is about 10?4, and it decreases by an order of magnitude after oxide dissolution. The plastic part of the strain is accompanied by the generation of dislocations in the most strained regions of a structure, i.e., at the interfaces between the porous layer and substrate in the vertical direction and between the central porous region and the pore-free edge in the horizontal plane. The dislocation density is ~104 cm?2. 相似文献
8.
This paper presents a novel method to fabricate separated macroporous silicon using a single step of photo-assisted electrochemical etching. The method is applied to fabricate silicon microchannel plates in 100 mm p-type silicon wafers, which can be used as electron multipliers and three-dimensional Li-ion microbatteries. Increasing the backside illumination intensity and decreasing the bias simultaneously can generate additional holes during the electrochemical etching which will create lateral etching at the pore tips. In this way the silicon microchannel can be separated from the substrate when the desired depth is reached, then it can be cut into the desired shape by using a laser cutting machine. Also, the mechanism of lateral etching is proposed. 相似文献
9.
M. M. Mezdrogina A. V. Abramov G. N. Mosina I. N. Trapeznikova A. V. Patsekin 《Semiconductors》1998,32(5):555-561
The decrease in the density of dangling silicon-silicon bonds in a-Si:H films as a result of annealing in an atomic-hydrogen atmosphere is determined by their density in the initial (nonannealed)
film. The change in the total hydrogen density in a-Si:H films, annealed in an atomic-hydrogen atmosphere, is determined by the type of silicon-hydrogen bonds and the impurity
content: The hydrogen content can decrease to 1 at. % in the presence of monohydride bonds (2020 cm−1) and no change is observed in the hydrogen content in the presence of oxygen (≲0.1 at. %). A decrease in the defect density
as a result of annealing in an atomic-hydrogen atmosphere is observed for all films. The Staebler-Wronski effect — AM-1 irradiation
for 10 h — is observed for all films irrespective of the total hydrogen density, the type of silicon-hydrogen bonds, and the
presence of oxygen.
Fiz. Tekh. Poluprovodn. 32, 620–626 (May 1998) 相似文献
10.
11.
The influence of voltage on photo-electrochemical etching(PEC) of macroporous silicon arrays(MSA) was researched.According to the theory of the space charge region,I-V scan curves and the reaction mechanism of the n-type silicon anodic oxidation in HF solution under different current densities,the pore morphology influenced by the working voltage were studied and analyzed in detail.The results show that increasing the etching voltage will lead to distortion of the pore morphology,decreasing etching volta... 相似文献
12.
Effects of nitrogen and argon as carrier gases and annealing ambients on the physical properties of PECVD silicon nitride 总被引:1,自引:0,他引:1
Q. A. Shams
W. D. Brown
《Microelectronics Journal》1989,20(6):49-59Deposition of memory quality plasma-enhanced chemically vapor deposited silicon nitride and post-deposition modification by annealing using argon and nitrogen for carrier gases and annealing ambients have been studied. Although similar memory performance can be achieved, the deposition power and NH3/SiH4 ratio required to do so are functions of the carrier gas used since nitrogen actively participates in the deposition process. Fourier transform infrared, ultraviolet and Auger data reveal that materials deposited with the two gases have similar physical properties although argon films are less dense and lose hydrogen at a higher rate when subjected to annealing. Post-deposition annealing can be used to enhance memory properties of the material provided that the anneal is accomplished at 475°C for 30 minutes. However, enhancement of memory performance by annealling occurs only if the nitride has been deposited using optimum deposition parameters. When annealing is performed in nitrogen. Auger data suggest that nitrogen can be supplied to, or removed from, the material depending on the anneal temperature. 相似文献
13.
This paper proposes the use of undoped hydrogenated microcrystalline silicon oxide (μc-SiOx:H) deposited on the n-μc-Si:H layer of amorphous silicon single-junction superstrate configuration thin-film solar cells produced through 40 MHz very high frequency plasma-enhanced chemical vapor deposition. Raman spectroscopy and optoelectronic analyses of the undoped μc-SiOx:H thin film revealed that adding a small amount of oxygen into a μc-network results in a low optical absorption, wide band gap, high optical band gap E04, high refractive index, reasonable conductivity, and crystalline volume fraction, which are advantageous properties in solar cells. Compared with a standard cell, the current density–voltage (J–V) characteristics of the cell with an undoped μc-SiOx:H/n-μc-Si:H structure showed an enhancement in short-circuit current density Jsc from 13.32 to 13.60 mA/cm2, and in conversion efficiency from 8.53% to 8.61%. The increased Jsc mechanism can be attributed to an improved light-trapping capability in the long wavelength range between 510 and 660 nm, as demonstrated by the external quantum efficiency. 相似文献
14.
A. Birner A. -P. Li F. Müller U. Gsele P. Kramper V. Sandoghdar J. Mlynek K. Busch V. Lehmann 《Materials Science in Semiconductor Processing》2000,3(5-6)
Photonic crystals consist of regularly arranged dielectric scatterers of dimensions on a wavelength scale, exhibiting band gaps for photons, analogous to the case of electrons in semiconductors. Using electrochemical pore formation in n-type silicon, we fabricated photonic crystals consisting of air cylinders in silicon. The starting positions of the pores were photolithographically pre-defined to form a hexagonal lattice of a=1.58 μm. The photonic crystal was microstructured to make the photonic lattice accessible for optical characterization. Samples with different filling factors were fabricated to verify the gap map of electric and magnetic modes using Fourier-transform infrared (IR) spectroscopy. The complete band gap could be tuned from 3.3 to 4.3 μm wavelength. We were able to embed defects such as waveguide structures or microcavities by omitting certain pores. We carried out transmission measurements using a tunable mid-IR optical parametric oscillator. The resonance is compared with theoretical expectations. 相似文献
15.
Platinum-silicon Schottky diodes on epitaxial layers have been subjected to argon ion bombardment, prior to metal evaporation, with doses in the 1014 ions/cm2 range and with energies between 1 and 3.5 KeV. By transient capacitance technique four electron traps have been found. The oxygen-vacancy pair (O-V) located at 0.17 eV below the conduction band, the double negatively charged divacancy (V-V=) at 0.23 eV and the phosphorous-vacancy pair (P-V) at 0.44 eV are observed. One more unknown level at 0.36 eV which could be oxygen-related is also found. 相似文献
16.
A. A. Dmitrievskiy N. Yu. Efremova A. V. Druzhkin T. O. Korostelyova D. G. Guseva 《Semiconductors》2014,48(9):1202-1204
The dependence of the microhardness H of macroporous silicon layers formed on the duration t an of electrochemical anodization at a constant current density of J = 20 mA/cm2 is studied. It is shown that the nonlinear run of the dependence H(t an) is due to the influence exerted on the microhardness not only by the surface density of pores, but also by the single-crystal base at L < 10h, where L and h are the thickness of the porous layer and the depth of indenter penetration, respectively. 相似文献
17.
I.R. Sanders B.D. Williams B.J. Smith J. Stephen G.W. Hinder 《Solid-state electronics》1977,20(8):703-707
Silicon wafers have been implanted with boron (3 × 1014 or 1 × 1015 ions cm?2) and with argon (up to 1 × 1015 ions cm?2). The energies were chosen to approximately superimpose the two impurity distributions. After the boron and argon implantations the sheet resistance of each wafer was measured following annealing in nitrogen at temperatures in the range 400–1050°C. The highest dose argon implantation produced an increase in sheet resistance which persisted throughout the entire temperature range. Lower argon doses produced a reduction in sheet resistance for anneal temperatures between 550 and 800°C. The magnitude of the reduction is a function of the boron and argon doses and of the anneal temperatures. The greatest reduction, observed after a 600°C anneal, was by a factor of 5.8. Above 800°C the low dose argon did not affect the sheet resistance.The observed reduction in sheet resistance is expected to lead to an improvement in metal to p-type silicon contacts. A particular application is in the contacts to resistors in fast bipolar logic circuits. As high electrical activity can be obtained at moderate annealing temperatures with combined boron and argon implantations, these implantations can be carried out at a late stage in an integrated circuit process schedule without the danger of additional movement of existing junctions. 相似文献
18.
《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1969,57(9):1484-1489
This paper describes the properties of active nickel centers in silicon. In particular, the role of nickel in both increasing and reducing minority carrier lifetime in silicon integrated circuits is described, and an assessment made of its use in this application. 相似文献
19.
G. V. Li T. L. Kulova V. A. Tolmachev A. V. Chernienko M. A. Baranov S. I. Pavlov E. V. Astrova A. M. Skundin 《Semiconductors》2013,47(9):1275-1281
Anodes based on a regular lattice of macroporous silicon with different periods, sizes, and shapes of pore cross sections are studied. The discharge capacity and its degradation during cycling (embedding and extraction of lithium) are examined. Scanning electron microscopy is used to analyze changes in the electrode structure upon the lithiation/delithiation of Si and to evaluate the elemental composition of the porous material. An ex situ morphological analysis of the electrodes demonstrates that, on the whole, the porous structure is preserved upon cycling and the thickness of silicon walls increases. The degree of Si-wall destruction depends on their initial thickness. Estimates show that the electrolyte reduction process mainly occurs according to the two-electron mechanism, with inorganic salts of lithium formed as a result. 相似文献
20.
Electrical activity and energy levels as well as diffusion properties of nickel in silicon have not yet been reliably established.
In this paper, we investigated the diffusion and the electrical properties of nickel in silicon to confirm that nickel is
electrically active and introduces one acceptor and one donor level by combined measurements of Hall coefficient and DLTS,
and measurements of the distribution of electrically active nickel in various silicon diodes by DLTS. The former experiments
show that bothn- andp- type silicon are compensated by nickel and that nickel introduces an acceptor level ofE
c-0.47 ± 0.04 eV and a donor level ofE
v +0.18 ± 0.02 eV. The concentrations of these two levels are almost identical over the diffusion temperatures from about 800
to 1100° C, indicating that these donor and acceptor levels are due to different charge states of the same nickel center.
In the distribution measurements of electrically active nickel in silicon diodes, we inspected how nickel can be observed
by DLTS. It was found that the nickel diffusion intop- n junction is rather complicated, the distribution profiles of nickel in the vicinity of thep- n junction being markedly influenced by an additional heating at elevated temperatures after the nickel diffusion. This gives
evidence that the difference in silicon devices used in various studies could give rise to different results. 相似文献