Material Characterizations for Semiconductor Technology

Ultra-Thin Film Analysis by Angled Resolved X-Ray Photoelectron Spectroscopy [ 下載 PDF ]

Fu-Ming Pan

The rapid scale-down of IC technology has made most contemporary analytical techniques difficult for the IC industry to meet the requirements of high spatial resolution and sensitivity at atomic levels. One of the critical metrology tasks is to measure the thickness of the ultra-thin silicon oxide dielectric layer of MOSFET devices and to characterize the interface property between novel high-k dielectric materials and the silicon substrate. In the article, the principle of thin film thickness measurement by angle resolved X-ray photoelectron spectroscopy (ARXPS) is described in detail. The relation between the film thickness and the XPS analysis angle is derived based on the inelastic mean free path of electrons traveling in solids. A few examples of interface characterization for nitrided silicon oxides and hafnium oxides are given to demonstrate the analytical potential of ARXPS for the sub-100 nm IC technology.

The Principle and Applications of Secondary Ion Mass Spectrometer [ 下載 PDF ]

Ching-Yuan Chen, Fu-Der Mai, Yong-Chien Ling

Time-of-flight secondary ion mass spectrometer (TOF-SIMS) is capable of simultaneously analyzing trace organic molecules and inorganic elements in mass ranging from hydrogen atom to synthetic and natural polymers with molecular weight up to ten thousands and more. TOF-SIMS could distinguish analytes with mass resolution different by 10000 at ppma to ppba sensitivity. Top monolayer atomic or molecular information could be determined by adjusting primary ion current density. Chemical images with lateral resolution less than 100 nm can be obtained by using Ga+ ion gun. The nm-scale depth profile and sub-µm area analysis capabilities inherent in TOF-SIMS extend its applicability to broad fields such as microelectronics, nano-technology, polymer science, life science technology, environmental analysis, medical technology and clinical diagnostics. TOF-SIMS could simultaneously provide critical chemical information and is a multi functional state-of-the-art instrument.

Introduction to Electric Scanning Probe Microscopy [ 下載 PDF ]

Mao-Nan Chang, Chih Yuan Chen, Fu-Ming Pan

Electrical scanning probe microscope (E-SPM), including scanning capacitance microscope (SCM) and conductive atomic force microscope (C-AFM), is one of the important tools for analyzing the electric properties of ultrathin dielectric layers. Working on bare gate dielectric layer, the conductive tip of the E-SPM allows us to obtain the electric characterization of nanometric areas, such as carrier concentration profile, leakage behavior and interface defects. In this article, we introduce the experimental set-up, the mechanism and the applications of E-SPM. Moreover, E-SPM related research fields have also been discussed.

The Industrial Applications of High Resolution Transmission Electron Microscopy on the III-V Compound Semiconductors [ 下載 PDF ]

Xing Jian Guo

III-V compound semiconductor device structures developed nowadays have generally been intended for the applications in very high speed electronic systems and in optical or opto-electronic systems. III-V compound semiconductor devices can obtain enhanced performance by combining two or more of these semiconductor compounds to form hetero-junctions or hetero-interfaces which are achievable by various type of epitaxial growth. In this paper, the fundamentals of high resolution transmission electron microscopy (HRTEM) are briefly given. Then several industrial applications of HRTEM on the III-V compound hetero-interface are illustrated. Furthermore, some TEM techniques related to HRTEM and the difficulties in III-V compound HRTEM investigations are discussed.

X-Ray Reflectivity in Advanced Semiconductor Applications [ 下載 PDF ]

Tzeng-Guang Tsai, Wen-Jih Lin, An-Thung Cho

This paper introduces the basic principle, technological progress and applications in advanced semiconductor processes of grazing incidence X-ray reflectivity.

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Design and Application of a Micro-Concave-Grating Demultiplexer [ 下載 PDF ]

Hui-Hsiung Lin, Jung Tim Lin, Yu-Jen Lin, Tong-Long Fu, Yu-Hsin Lin, Mao-Hong Lu

In this paper a novel micro-concave-grating that combines the both function of a micro-plano-grating and a concave mirror (or focusing lens) is designed with the Rowland circle concept. Consequently, the wavelength division and the focusing on image plane can be simultaneously realized with such a device. The approach of expanding the light-path-function, ray tracing, Huygens diffraction integral, and rigorous coupled wave theory are used in designing the micro-concave-grating and analyzing its beam diffraction characteristics. A device used for the wave division demultiplexing of fiber communication with 81 channels about 0.181nm FWHM, and less than 0.39nm channel spacing has been successfully carried out. This micro-concave-grating for DWDM was fabricated by ICP-RIE advanced silicon etching (ASE) technique with a sidewall perpendicularity of 90±1° and an average surface roughness of less than 5nm. Besides, a micro-concave-grating working in the visible wavelength range 380 – 780 nm with resolution of 0.18 – 0.40 nm and channel spacing of about 1nm for biomedical applications is also presented.

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The Machining Effects on Form Error of Aspherical Surface [ 下載 PDF ]

Kuo-Cheng Huang, Ho-Chiao Chuang, Pei-Lum Tso, Ching-Hsiang Kuo

The purpose of this research is to study about the effect of various parameters on the aspheric lens during the form generating and polishing process. By applying the experiment results, an effective method is proposed for improving the form error and the surface roughness. For the form generating process, we discussed the effect of the lens form error and surface roughness by altering the angle of inclination between the cup wheel and the lens surface, and also the workpiece rotational speed. For the lapping process, we discussed the effect of the lens form error and surface roughness by applying the different abrasive grain size and lapping pads. In addition, we also concern the uniformity of the lapping pressure distribution. For the polishing process, our research is focused on improving the lens surface roughness.

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Coincidence Techniques as Applied to Chemical Physics (II) [ 下載 PDF ]

Kaidee Lee

Various coincidence techniques pertaining to electron impact excitation and photoabsorption in the realm of chemical physics are presented, in an attempt to elucidate the roles they play in unraveling the intricate decay paths of excited states. This article intends to convey, via the diversity of the coincidence techniques mentioned, the broader stage and wider vistas created for them by synchrotron soft X-ray and X-ray chemical physics research in the last ten years. The latter part of the article discusses the two-dimensional position detection schemes introduced into the coincidence techniques gradually in recent years, and the envisioned trailblazing role played by real-time ion imaging and the associated momentum coincidence, resulting from integration of the former two, in the study of molecular fragmentation dynamics.

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Introduction to Molecular Imprinting Technique — Synthesis of Man-Made Mimics of Antibodies [ 下載 PDF ]

Tzong-Rong Ling, Yau-Ching Tsai, Tse-Chuan Chou

The molecular imprinting technique has been rapidly developed to create recognition materials that can be applied to several fields such as stationary phase materials in chromatography to separate enantiomers, selective reaction in catalysis, analytes recognition in sensors, etc. The technique can be used to prepare the molecularly imprinted polymer (MIP) with predetermined affinities for amino acids, peptides, proteins, nucleotides, carbohydrates, various drugs (e.g. opiates, alkaloids, antibiotics), steroids, herbicides, metal ions, and a number of miscellaneous organic compounds. Several methods have been reported to synthesize the MIP with the capability of molecular size and shape or binding site recognition. In the text, we will introduce the principle of MIP preparation and some typical issues approaching by selecting functional monomers to interact with molecules templates as following: molecular imprinting with covalent or non-covalent binding, molecular imprinting with metal-ion monomer or metal-ion templates, molecular imprinting with inorganic monomer or microoganism templates. The challenging problems of MIP were also discussed.