Properties of high k gate dielectric gadolinium oxide deposited on Si(100) by dual ion beam deposition (DIBD)

Gadolinium oxide thin films have been prepared on silicon (100) substrates with a low-energy dual ion-beam epitaxial technique. Substrate temperature was an important factor to affect the crystal structures and textures in an ion energy range of 100-500 eV. The films had a monoclinic Gd2O3 structure with preferred orientation ((4) over bar 02) at low substrate temperatures. When the substrate temperature was increased, the orientation turned to (202), and finally, the cubic structure appeared at the substrate temperature of 700 degreesC, which disagreed with the previous report because of the ion energy. The AES studies found that Gadolinium oxide shared Gd2O3 structures, although there were a lot of oxygen deficiencies in the films, and the XPS results confirmed this. AFM was also used to investigate the surface images of the samples. Finally, the electrical properties were presented. (C) 2004 Elsevier B.V. All rights reserved.

Mn implanted GaAs by low energy ion beam deposition

High dose Mn was implanted into semi-insulating GaAs substrate to fabricate embedded ferromagnetic Mn-Ga binary particles by mass-analyzed dual ion beam deposit system at room temperature. The properties of as-implanted and annealed samples were measured with X-ray diffraction, high-resolution X-ray diffraction to characterize the structural changes. New phase formed after high temperature annealing. Sample surface image was observed with atomic force microscopy. All the samples showed ferromagnetic behaviour at room temperature. There were some differences between the hysteresis loops of as-implanted and annealed samples as well as the cluster size of the latter was much larger than that of the former through the surface morphology. (C) 2004 Elsevier B.V. All rights reserved.

FexSi grown with mass-analyzed low-energy dual ion beam deposition

Heavily iron-implanted silicon was prepared by mass-analyzed low-energy dual ion beam deposition technique. Auger electron spectroscopy depth profiles indicate that iron ions are shallowly implanted into the single-crystal silicon substrate and formed 35 nm thick FexSi films. X-ray diffraction measurements show that as-implanted sample is amorphous and the structure of crystal is partially restored after as-implanted sample was annealed at 400degreesC. There are no new phases formed. Carrier concentration depth profile of annealed sample was measured by Electrochemical C-V method and indicated that FexSi film shows n-type conductivity while silicon substrate is p-type. The p-n junction is formed between FexSi film and silicon substrate showing rectifying effect. (C) 2003 Elsevier B.V. All rights reserved.

强CO_2激光退火时离子注入Si的光学性质

本文测量了砷离子(As~+)注入的Si在连续CO_2激光辐照下光的椭圆偏振参数、反射率、表面薄层电阻率随时间的变化。从(?)、△、R、ρ的变化看出Si注入层的激光退火是在一定的时间、温度条件下迅速完成的。

扩硼Si在连续CO_2激光辐照后的特性

本文研究了高温高浓度扩硼Si在连续CO_2激光辐照后表面薄层电阻随激光功率密度和扫描速度的变化.实验发现,一定功率密度和扫描速度的CO_2激光辐照可使扩硼Si的载流子面密度提高到原来的一倍半到三倍左右.

强激光辐照下集成电路Si片的椭圆偏振光研究

<正> 用强激光辐照的方法对集成电路用的离子注入Si进行退火是近几年大力研究的一个问题。至今为止绝大多数的激光退火都是采用红宝石、YAG、氩离子等波长较短的激光器。实验虽已证实CO_2激光的退火效果完全可与其他激光比美,然而研究者甚少,且基本上限于最后结果的观测。激光作为电磁波,其趋肤深度

强CO_2激光辐照下离子注入Si反射率的动态干涉效应

本文从理论和实验研究了连续CO_2激光辐照下磷离子注入Si对He-Ne激光束反射率呈现的动态干涉效应。从反射强度随时间的变化看出,Si片离子注入层固相外延的速率在整个再结晶过程中是不均匀的。

离子注入Si在连续CO_2激光退火时的动态反射特性

本文用红外探测器测量了注磷Si在高功率连续CO_2激光辐照下反射率随时间的变化,发现在激光加热和随后冷却的过程中均出现不可逆的反射率跃升现象,这说明Si的表面载流子浓度也有着类似的变化。

力学量与国际单位制(SI)

<正> 过去我国采用的基本计量单位是米制(即公制),而今后我国将逐步推行国际单位制.采用国际单位制,牵涉较多的部门主要是工业技术、生产和教学等方面,牵涉较多的学科主要是力学专业.为此,在这里介绍国际单位制和有关的力学量单位.国际单位制(Système International d'Unités,简称SI)是一九六○年第十一届国际计量大会(CGPM)通

Alejandra Pizarnik: "Si no me escribo soy una ausencia"

[ES] Este trabajo propone una lectura de los seis primeros cuadernos del diario que Alejandra Pizarnik escribió a lo largo de toda su vida, desde los 18 años y hasta que murió a la edad de 36. El análisis de estos cuadernos, escritos entre 1954 y 1958, nos permite recorrer el itinerario que Alejandra Pizarnik realiza por la cuestión genérica, la cuestión nacional y la cuestión sexual. Desde su experiencia en cuanto sujeto, la escritura registra esta primera fase en la construcción del yo que Pizarnik desea para su diario. Esta fase, que se puede denominar etapa-derribo, está dominada por el desafío a las ideas del discurso hegemónico. Una vez haya resuelto este escollo en la construcción del yo de su diario, la escritura de Pizarnik no volverá sobre estos temas. Sin embargo, la búsqueda el “verdadero” yo se registra como proceso en el que a un movimiento de construcción del yo, le sigue un movimiento de destrucción de lo que las palabras han conformado, en secuencias en las que la apelación a la mentira de lo escrito o la desconfi anza en la capacidad del lenguaje para expresarlo, son la pauta de dicha escritura.