Determination of the intrinsic carrier concentration in InSb by helicon waves

The intrinsic carrier concentration in InSb was determined, between 246 and 370 K, by a helicon method consisting of a microwave interferometer at 34 GHz. The accuracy of the carrier concentration is between 1–2%. The influence of experimental parameters on the determination of the carrier concentration and the mobilities of both electrons and holes is discussed in detail. Comparing the data obtained for the carrier concentration with Hall effect measurements a small difference of the absolute values is found. The band-gap deduced is in agreement with the Hall effect measurements.     

Wide frequency range P relaxation in the ion conducting glass LiPO3

Spin-lattice relaxation studies on the stationary ³¹P nucleus have been performed in order to investigate to which extent the dynamics of the mobile lithium ions are reflected in the behavior of the glassy network. The temperature dependence of the ³¹P relaxation, which is governed by the heteronuclear dipole-dipole interaction between lithium and phosphorus, can be described in terms of a Gaussian distribution of activation energies and that over a wide frequency range from about 34 kHz to 81 MHz. A relaxation rate maximum, which provides useful information about correlation times and activation energies of the lithium-ion diffusion process, could only be observed in the rotating frame relaxation measurements.     

高电荷态离子40Arq+与Si表面作用中的电子发射产额

报道了在兰州重离子加速器国家实验室电子回旋共振离子源原子物理实验平台上，用高电荷态⁴⁰Ar^q+(1≤q≤12)离子作用于半导体Si固体表面时的电子发射产额实验测量.实验中，通过改变炮弹离子的电荷态和引出电压选取其不同的势能和动能，系统地研究了入射离子势能沉积和与其在固体中的电子能损对表面电子发射产额的贡献.结果表明，作为引起表面电子发射的两个主要因素，单离子的电子发射产额与炮弹离子在固体表面的势能沉积和电子能损都有近似的正比关系.     

Determination of the thickness and density of the ion bombardment induced altered layer in SiC by means of reflection electron energy loss study

The steady state surfaces of ion bombarded 3C-, 4H- and 6H-SiC samples were studied by means of reflected electron energy loss spectroscopy (REELS). The REELS exhibit a well-defined loss peak in the region of about 20 eV. The position of the maximum of the loss peak depends on the bombarding ion energy (decreasing with increasing ion energy), and on the primary electron beam energy (increasing with increasing primary energy). This behavior can be explained if we suppose that the plasmon energy in the altered layer (produced by ion bombardment) is different from that of the unaltered bulk. In this case the measured loss peak is the sum of two overlapping plasmon peaks. With modeling the system as a homogeneous altered layer and a homogeneous unaltered substrate the plasmon energy in the altered layer was derived to be 19.8 eV. The large change of the plasmon energy with respect to the bulk value of 23 eV is explained by a thin low density overlayer on the surface of the sample produced by the ion bombardment.     

Kinetic energy and charge state effects in the X-ray emission of Mo surface induced by Xe q + ( q = 25, 29) ions

L-shell X-ray spectra of Mo surface induced by Xe²⁵⁺ and Xe²⁹⁺ were measured. The X-ray intensity was obtained in the kinetic energy range of the incident ions from 350 to 600 keV. The relationship of X-ray intensity with kinetic energy of the projectile and its charge state were studied, and the simple explanation was given. Supported by the Science and Technology Ministry Foundation of China (Grant No. 2002CCA00900) and the Foundation of National Key Laboratory of Vacuum & Cryogenics Technology and Physics