Study of nucleon spin-dependent properties in the resonance region

In this paper, the spin-dependent structure functions of nucleon g ₁, and photoabsorption cross sections σ_1/2, σ_3/2 and σ_T in the resonance region are estimated based on the constituent quark model and the properties of the five phenomenological Breit-Wigner resonances P ₃₃(1232), S ₁₁(1535), D ₁₃(1520), P ₁₁(1440), and F ₁₅(1680). Our results are compared to the recent E143 data of the polarized structure functions g ₁(W ², Q ²) at points Q ²=0.5 GeV² and Q ²=1.2 GeV² and the data of the total inclusive photoabsorption cross sections. Received: 7 October 1997     

Monte Carlo analysis of electron scattering in microstructure processes in the 0.2 μm region

Summary Theoretical understanding of electron scattering phenomena is essential to the implementation of X-ray lithography. In this paper we theoretically investigate electron scattering effects in X-ray mask-making, by means of a subtractive process, in the 0.2 μm region. The results of Monte Carlo simulation are utilized in order to calculate radial absorbed energy distributions and resist development profiles with respect to some cases of practical interest. Relevant process variables are considered, such as electron-beam energy (10 to 30 keV) and spot sizes. The results show how, by choosing appropriate working conditions, high-resolution patterns can be obtained. Favourable process conditions are found at the low electron energy limit. However, it is shown that suitable electron-beam spot sizes are required in order to take fully advantage of the favourable properties of the scattering. Research supported by Finalized Project MA.D.E.S.S. of Consiglio Nazionale delle Ricerche.     

Supersonic molecular beam growth of thin films of organic materials: A novel approach to controlling the structure,morphology, and functional properties

Thin films of semiconducting molecular materials can be grown with a seeded supersonic molecular beam epitaxy (SuMBE), which provides unprecedented control over structural, morphological, and, therefore, functional properties. This novel technique of deposition takes full advantage of its ability to regulate the initial state of the molecular precursors in the beams and, in particular, the kinetic energy, to control the morphology, structure, and functional properties of growing films. This article reviews the state of the art of SuMBE, discussing the basic aspects of the technique and the major achievements so far. The major results obtained with respect to growth on dielectrics and metal substrates of films of oligothiophenes and pentacene and with respect to the codeposition of phthalocyanines and fullerenes are discussed and compared with the state of the art of more conventional organic molecular beam deposition. The potential impact of SuMBE in the field of π‐conjugated materials and devices is also examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2501–2521, 2003     

Si衬底上生长的GaAs薄膜中深中心发光的温度效应

测量了Ｓｉ衬底上生长的ＧａＡｓ薄膜中与深中心有关的发光带的变温光谱，研究了０．７８ｅＶ、０．８４ｅＶ和０．９３ｅＶ发光带的峰值位置和发光强度随着温度的变化关系，发现它们的发光强度随温度的变化服从描述非晶半导体中局域态发光的公式。最后讨论了这些发光带的来源。     

Modelling and analysis of a non-regular electronic circuit via a variational inequality formulation

In this paper, we present a new and alternative mathematical modelling and analysis methodology for a class of non-regular electronic circuits through a rectifier-stabilizer circuit using the superpotentiel of Moreau and the theory of variational inequalities. This methodology is suitable for engineers to study a large class of applications.