DETERMINATION OF ULTRA TRACE LEVEL METALLIC IMPURITIES IN SEMICONDUCTOR MATERIALS BY ICP-MS

Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｓｅｍｉｃｏｎｄｕｃｔｏｒｄｅｖｉｃｅｓｈａｖｅｂｅｅｎｗｉｄｅｌｙｕｓｅｄｆｏｒｖａｒｉｏｕｓａｐｐｌｉｃａｔｉｏｎｓａｎｄｂｅｃｏｍｅｉｎｄｉｓｐｅｎｓａｂｌｅｆｏｒｃｉｖｉｌｉｚｅｄｌｉｆｅ ｓｔｙｌｅ.Ａｖａｒｉｅｔｙｏｆｃｈｅｍｉｃａｌｓａｎｄｍａｔｅｒｉａｌｓａｒｅｕｓｅｄｉｎｐｒｏｃｅｓｓｏｆｍａｎｕｆａｃｔｕｒｉｎｇｏｆｓｅｍｉｃｏｎｄｕｃｔｏｒｄｅｖｉｃｅｓ.Ａｔｒａｃｅｌｅｖｅｌｏｆｍｅｔａｌｌｉｃｉｍｐｕ ｒｉｔｉｅｓｉｎｔｈｅｃｈｅｍｉｃａｌｓａｎ…     

Diffraction Properties of Field Adjustable Polymer Network Stabilized Liquid Crystal Grating

Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｄｕｅｔｏａｎｉｓｏｔｒｏｐｉｃｏｐｔｉｃａｌａｎｄｅｌｅｃｔｒｉｃａｌｐｒｏｐｅｒｔｉｅｓ,ｔｈｅｏｐｔｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｌｉｑｕｉｄｃｒｙｓｔａｌｓｃａｎｂｅａｄｊｕｓｔｅｄｂｙｅｌｅｃｔｒｉｃｆｉｅｌｄ,ａｎｄｔｈｕｓｔｈｅｄｉｆｆｒａｃｔｉｏｎｇｒａｔｉｎｇｆａｂｒｉｃａｔｅｄｕｓｉｎｇｌｉｑｕｉｄｃｒｙｓｔａｌｓｃａｎｂｅａｄｊｕｓｔａｂｌｅｂｙｅｌｅｃｔｒｉｃｆｉｅｌｄ．Ｓｕｃｈｄｅｖｉｃｅｓｈａｖｅｐｏｔｅｎｔｉａｌａｐｐｌｉｃａｔｉｏｎｓ…     

PROGRESS IN PHYSICS(Quarterly Review Journal of Physics)

ＰｒｏｇｒｅｓｓＩｎＰｈｙｓｉｃｓｉｓｐｕｂｌｉｓｈｅｄｂｙＴｈｅＣｈｉｎｅｓｅＰｈｙｓｉｃａｌＳｏｃｉｅｔｙｔｈｒｏｕｇｈＴｈｅＪｉａｎｇｓｕＰｒｅｓｓｆｏｒＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ .Ｔｈｉｓｊｏｕｒｎａｌｃａｒｒｉｅｓｒｅｖｉｅｗａｒｔｉｃｌｅｓａｂｏｕｔｎｅｗａｃｈｉｅｖｅｍｅｎｔｓａｎｄｄｅｖｅｌｏｐｍｅｎｔｓｉｎａｌｌａｓｐｅｃｔｓｏｆｐｈｙｓｉｃｓ.Ｉｔｃｏｖｅｒｓｆｒｏｎｔｉｅｒａｒｅａｓｏｆｐｈｙｓｉｃｓａｓｗｅｌｌａｓｎｅｗｔｒｅｎｄｓｉｎｔｈｅｏｌｄｅｒｂｒａ…     

PROGRESS IN PHYSICS(Quarterly Review Journal of Physics)

ＰｒｏｇｒｅｓｓＩｎＰｈｙｓｉｃｓｉｓｐｕｂｌｉｓｈｅｄｂｙＴｈｅＣｈｉｎｅｓｅＰｈｙｓｉｃａｌＳｏｃｉｅｔｙｔｈｒｏｕｇｈＴｈｅＪｉａｎｇｓｕＰｒｅｓｓｆｏｒＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ .Ｔｈｉｓｊｏｕｒｎａｌｃａｒｒｉｅｓｒｅｖｉｅｗａｒｔｉｃｌｅｓａｂｏｕｔｎｅｗａｃｈｉｅｖｅｍｅｎｔｓａｎｄｄｅｖｅｌｏｐｍｅｎｔｓｉｎａｌｌａｓｐｅｃｔｓｏｆｐｈｙｓｉｃｓ.Ｉｔｃｏｖｅｒｓｆｒｏｎｔｉｅｒａｒｅａｓｏｆｐｈｙｓｉｃｓａｓｗｅｌｌａｓｎｅｗｔｒｅｎｄｓｉｎｔｈｅｏｌｄｅｒｂｒａ…     

Photoacoustic Tomography of Biological Sample Using Phase-controlled Focus Algorithm

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｏｐｔｉｃａｌｔｏｍｏｇｒａｐｈｙｏｆｓｃａｔｔｅｒｉｎｇｍｅｄｉａｓｕｃｈａｓｂｉｏｌｏｇｉｃａｌｔｉｓｓｕｅｓｉｓａｎｉｎｃｒｅａｓｉｎｇｌｙａｃｔｉｖｅｆｉｅｌｄｂｅｃａｕｓｅｏｆｉｔｓａｄｖａｎｔａｇｅｓｉｎｎｏｎｉｎｖａｓｉｏｎ ,ｎｏｎｉｏｎｉｚａｔｉｏｎａｎｄｏｐｔｉｃａｌｃｏｎｔｒａｓｔｗｈｅｎｉｔｉｓｕｓｅｄｆｏｒｂｉｏｍｅｄｉｃａｌｄｉａｇｎｏｓｉｓ[1] .Ｔｈｅｍｅｃｈａｎｉｓｍｏｆｏｐｔｉｃａｌｉｍａｇｉｎｇｉｓｂａｓｅｄｏｎｔｈｅｄｉｆｆｅｒｅ…     

Fiber-optic Based Scanning Confocal Microscopic Interferometer for the Measurement of Surface Topography

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｔｈｅｒｅｉｓａｎｉｎｃｒｅａｓｉｎｇｒｅｑｕｉｒｅｍｅｎｔｆｏｒｔｈｅｐｒｅｃｉｓｅｍｅａｓｕｒｅｍｅｎｔｏｆｔｈｅｓｕｒｆａｃｅｍｉｃｒｏｓｔｒｕｃｔｕｒｅｓｏｎｌａｒｇｅ ｓｃａｌｅｏｂｊｅｃｔｓｏｆｃｏｍｐｌｅｘｓｈａｐｅｗｉｔｈｓｔｅｅｐｓｕｒｆａｃｅｓｌｏｐｅｓ .Ｔｈｅｓｔｙｌｕｓｉｎｓｔｒｕｍｅｎｔｉｓｗｉｄｅｌｙｕｓｅｄａｓｔｈｅｐｒａｃｔｉｃａｌｍｅｔｈｏｄ ,ｂｕｔｔｈｅｍｅａｓｕｒｅｍｅｎｔａｃｃｕｒａｃｙｉｓｌｉｍｉｔｅｄｄｕｅｔｏｉｔｓｃｏｎ…     

Optical Properties of Yb~(3 ) Doped Bi_2O_3-3B_2O_3 Glass

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｔｈｅｏｐｔｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｇｌａｓｓｅｓ,ｓｕｃｈａｓｇｌａｓｓｔｒａｎｓｐａｒｅｎｃｙａｎｄｔｈｅｉｒｃａｐａｂｉｌｉｔｙｔｏａｃｃｅｐｔｒａｒｅｅａｒｔｈｉｏｎｓａｓｔｈｅｌｕｍｉｎｅｓｃｅｎｔｃｅｎｔｅｒｓ ,ａｒｅｅｓｓｅｎｔｉａｌｆｏｒｔｈｅｉｒｕｓｅｉｎｇｌａｓｓｌａｓｅｒｔｅｃｈｎｏｌｏｇｙ .Ｄｕｒｉｎｇｔｈｅｌａｓｔｆｅｗｙｅａｒｓ,ａｌａｒｇｅｖａｒｉｅｔｙｏｆｉｎｏｒｇａｎｉｃ ｇｌａｓｓｅｓｈａｖｅｂｅｅｎｄｅｖｅｌｏｐ…     

Polarization of Tapered Semiconductor Travelling-Wave Amplifiers

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｔａｐｅｒｅｄｓｅｍｉｃｏｎｄｕｃｔｏｒｔｒａｖｅｌｌｉｎｇ ｗａｖｅａｍｐｌｉｆｉｅｒｓｎｏｗａｒｅｏｎｅｏｆｔｈｅｉｍｐｏｒｔａｎｔｒｅｓｅａｒｃｈｓｕｂｊｅｃｔｓｉｎｓｅｍｉｃｏｎｄｕｃｔｏｒｏｐｔｏ ｅｌｅｃｔｒｏｎｉｃｓ.Ｂａｓｅｄｏｎｔｈｅｓｅｒｅｓｅａｒｃｈｒｅｓｕｌｔｓ,ｔｈｅｃｏｕｐｌｉｎｇｅｆｆｉｃｉｅｎｃｙｂｅｔｗｅｅｎｆｉｂｅｒａｎｄｓｅｍｉｃｏｎｄｕｃｔｏｒａｍｐｌｉｆｉｅｒ,ｔｈｅｌｉｆｅｔｉｍｅｏｆｄｅｖｉｃｅｓａｎｄｔｈｅ ｐｅｒｆｏｒｍ…     

Spectroscopic Properties of Yb 3 doped Borate Glasses

Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｔｈｅｅｍｉｓｓｉｏｎｃｒｏｓｓｓｅｃｔｉｏｎａｎｄｆｌｕｏｒｅｓｃｅｎｃｅｌｉｆｅｔｉｍｅａｒｅｆｕｎｄａｍｅｎｔａｌｓｐｅｃｔｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｌａｓｅｒｇｌａｓｓｅｓ．ＴｈｅｓｅｐｒｏｐｅｒｔｉｅｓｃａｎｂｅｃａｌｃｕｌａｔｅｄｕｓｉｎｇｉｎｔｅｎｓｉｔｙｐａｒａｍｅｔｅｒｓΩｔ（ｔ＝２,４,６）ｂａｓｅｄｏｎｔｈｅＪｕｄｄＯｆｅｌｔｔｈｅｏｒｙ［１,２］．Ｔｈｅｏｐｔｉｃａｌａｎｄｓｐｅｃｔｒｏｓｃｏｐｉｃｐｒｏｐｅｒｔｉｅｓｏｆｒａ…     

Fiber Ring Laser In-cavity Phase Modulation

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｉｎｏｐｔｉｃａｌｃｏｍｍｕｎｉｃａｔｉｏｎ ,ｏｐｔｉｃａｌｓｅｎｓｉｎｇｓｙｓｔｅｍ ,ａｎｄｈｉｇｈｒｅｓｏｌｕｔｉｏｎｓｐｅｃｔｒｏｓｃｏｐｅ ,ｌａｓｅｒｓｏｕｒｃｅｓｗｉｔｈｎａｒｒｏｗｌｉｎｅｗｉｄｔｈａｒｅａｌｗａｙｓｎｅｃｅｓｓａｒｙ .Ｆｉｂｅｒｒｉｎｇｌａｓｅｒｓａｎｄａｃｔｉｖｅｆｉｂｅｒｒｉｎｇｒｅｓｏｎａｔｏｒｆｉｌｔｅｒｓｍａｙｂｅａｐｐｌｉｅｄｔｏｐｒｏｄｕｃｅｎａｒｒｏｗｌｉｎｅｗｉｄｔｈｌａｓｅｒｓ .Ｂｅｃａｕｓｅｔｈｅｃｈａｒａｃｔｅ…     

Discussion for the Semi-infinite Medium Approximation and the Thermal Diffusion Velocity in Laser Heat Treatment

It is a conventional method to regard laser-iradiated object as a semi-infinite medium with invariable thermal physical property parameters for approximate analyses of thermal acting of laser heat treatment. So far, 2 and have been taken as the thermal diffusion distance and the thermal diffusion velocity respectively, at the time t after heat fluctuation in materials with a thermal diffusion coefficient α, and as a result, the feasibility of the approximately estimating method about semi-infinite medium is judged. This paper indicates that, due to quantitative investigation of heat energy diffusion, the thermal diffusion distance of 3 and the thermal diffusion velocity of 1.5 can more accurately describe the physical process of heat conduction. Finally, an applied example of approximately estimating the temperature field of laser heat treatment is presented.     

含双圆柱亚表面缺陷板条材料的表面温度分布

基于非傅里叶热传导方程,采用复变函数法和镜像法,研究了含双圆柱亚表面缺陷板条材料热波散射的温度场,并给出了热波散射温度场的解析解。分析了入射波波数、热扩散长度、缺陷的埋藏深度以及板条材料的厚度等对板条表面温度分布的影响。温度波由调制光束在材料表面激发,缺陷表面的边界条件为绝热。该分析方法和数值结果可为工程材料结构的传热分析、热波成像和材料内部缺陷评估,以及热物理反问题研究提供参考。     

Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation

The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic(MHD) heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented,taking into account thermal radiation and internal heat genberation/absorbtion.The stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation point.The Rosseland approximation is used to describe the radiative heat flux in the energy equation.The governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung-Kutta method with the shooting technique.A comparison with previously published work has been carried out and the results are found to be in good agreement.The results are analyzed for the effect of different physical parameters,such as the variable viscosity and thermal conductivity,the ratio of free stream velocity to stretching velocity,the magnetic field,the porosity,the radiation and suction/injection on the flow,and the heat and mass transfer characteristics.The results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = 1.In addition,the imposition of fluid suction increases both the rate of heat and mass transfer,whereas fluid injection shows the opposite effect.     

脉冲激光烧蚀过程中靶材表面熔融前温度分布与激光功率密度分布的研究

用较为符合实际的高斯分布表示了脉冲激光输出功率密度分布，讨论了脉冲激光功率密度分布函数形状变化对烧蚀过程中靶材表面熔融前温度分布的影响。建立了考虑热源项的热传导方程，并给出了相应的边界条件。以Si为例，用有限差分方法模拟了温度随时间、位置的变化规律，模拟过程中强调了对边界条件的处理，使整体截断误差保持最小。通过改变脉冲激光功率密度分布函数的形状，分析了温度分布的变化。结果表明，相比恒定脉冲功率密度输出，功率密度高斯分布的激光束与靶材作用时高温阶段的温度变化率变大，靶材表面熔融时刻热扩散距离增加；当激光器上升沿变陡时，在有效作用时间内温度上升得更快，对加工区域周围热效应的影响明显减弱，而热扩散距离变小。     

短脉冲激光与介质相互作用的扩散模型

推导了扩散近似方程,通过半无限大均匀介质计算,用扩散理论分析解验证了数值方法的有效性.模拟了光在非均匀介质内的传输过程,给出了介质内光通量随时间变化的空间分布.结果表明,该基于扩散模型的数值方法能够模拟短脉冲光在强散射介质中的传播过程以及漫散射光的时间变化特性,并且借助于光通量空间分布能够准确模拟非均匀介质内内含物的位置.     

Fractional Order Theory in a Semiconductor Medium Photogenerated by a Focused Laser Beam

In this paper, the fractional order theory has been applied for thermal, elastic and plasma waves to determine the carrier density, displacement, temperature and stress in a semiconductor medium. The thermal, elastic and plasma waves in a semi-infinite medium photogenerated by a focused laser beam were analyzed. The Laplace transformation is used to express the governing equation and solved analytically by applying eigenvalue approach methodology in that domain. A semiconducting material like as silicon was considered. According to the numerical results and graphics, the fractional order parameter and thermal relaxation time may play an important role in the behavior of all physical quantities.     

Thermal affected zone obtained in machining steel XC42 by high-power continuous CO2 laser

A high-power continuous CO₂ laser (4 kW) can provide energy capable of causing melting or even, with a special treatment of the surface, vaporization of an XC42-steel sample. The laser–metal interaction causes an energetic machining mechanism, which takes place according to the assumption that the melting front precedes the laser beam, such that the laser beam interacts with a preheated surface whose temperature is near the melting point. The proposed model, obtained from the energy balance during the interaction time, concerns the case of machining with an inert gas jet and permits the calculation of the characteristic parameters of the groove according to the characteristic laser parameters (absorbed laser energy and impact diameter of the laser beam) and allows the estimation of the quantity of the energy causing the thermal affected zone (TAZ). This energy is equivalent to the heat quantity that must be injected in the heat propagation equation. In the case of a semi-infinite medium with fusion temperature at the surface, the resolution of the heat propagation equation gives access to the width of the TAZ.     

水力入口段对流体直接冷却片状激光器热效应的影响

流体直接冷却Nd:YAG片状激光器系统中,流体流经增益介质时存在水力入口段,使用Ansys仿真软件,讨论了不同水力入口段距离对流体热交换系数的影响,并在此基础上,将水力入口段距离进行分类,分析了水力入口段距离对热应力以及光束传输的影响;模拟了不同冷却液的冷却效果;研究了流体处于不同流动状态时,水力入口段距离与流体热交换系数的关系,以及水力入口段距离与增益介质温度分布的关系;得到了这种高功率激光器冷却系统中,最佳水力入口段距离的范围。结果表明:流体流经增益介质时,不同的水力入口段距离只是规律性地移动了流体的热交换系数曲线,因此,避开流体热交换系数曲线中变化较大的区域,即0～2.25 mm范围内的水力入口段距离,可实现介质内更小的温度梯度,同时降低热应力以及波前畸变,从而实现更好的冷却效果。     

Thermal Analysis of Gold Nanorods Heated with Femtosecond Laser Pulses

We present an axisymmetric computational model to study the heating processes of gold nanoparticles, specifically nanorods, in aqueous medium by femtosecond laser pulses. We use a two-temperature model for the particle, a heat diffusion equation for the surrounding water to describe the heat transfer processes occurring in the system, and a thermal interface conductance to describe the coupling efficiency at the particle/water interface. We investigate the characteristic time scales of various fundamental processes, including lattice heating and thermal equilibration at the particle/surroundings interface, the effects of multiple laser pulses, and the influence of nanorod orientation relative to the beam polarization on energy absorption. Our results indicate that the thermal equilibration at the particle/water interface takes approximately 500 ps, while the electron-lattice coupling is achieved at approximately 50 ps when a 48×14 nm gold nanorod is heated to a maximum temperature of 1270 K with the application of a laser pulse having 4.70 J/m(2) average fluence. Irradiation by multiple pulses arriving at 12.5 ns time intervals (80 MHz repetition rate) causes a temperature increase of no more than 3 degrees during the first few pulses with no substantial changes during the subsequent pulses. We also analyze the degree of the nanorods' heating as a function of their orientation with respect to the polarization of the incident light. Lastly, it is shown that the temperature change of a nanorod can be modeled using its volume equivalent sphere for femtosecond laser heating within 5-15% accuracy.     

亚表面双球孔洞的热波散射与温度分布

基于非Fourier热传导方程,采用波函数展开法,对含双球形孔洞缺陷的半无限体材料内部的热波散射与温度分布进行了研究,给出了材料内部任一点温度的解析解和表面温度分布的数值计算结果。分析了孔洞的几何参数和物理参数对金属材料表面温度分布的影响。结果表明:相对热扩散长度、入射波波数和埋藏深度对表面温度分布的影响比较大,当孔洞间距较大时,可以忽略孔洞之间的热波散射。