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Leading NSRRC to Achieve Excellence and Built to Last –- Dr. Chia-Hung Hsu, Director of National Synchrotron Radiation Research Center [ 下載 PDF ]

Claire Lin

Semiconductor Process Inspection Equipment and in-situ Technology

Special Issue Introduction of “Semiconductor Process Inspection Equipment and in-situ Technology” [ 下載 PDF ]

Chi-Chung Kei

Novel DUV Wavelength-scanning Scatterometry and System for Sub-micron Scale High-aspect-ratio Microstructures [ 下載 PDF ]

Fu-Sheng Yang, Yuan-Ci Lin, Min-Ru Wu, Yen-Hung Hung, Bo-Chen Kuo, Liang-Chia Chen

With the development of semiconductor 3D packaging technology, high aspect ratio RDL and TSV structures have become critical signal transmission interfaces between layers. Therefore, there is an urgent demand for a comprehensive measurement technology to measure the critical dimensions of high aspect ratio structures accurately. This study proposes a hybrid metrology measurement system that combines DUV reflectometry and wavelength-scanning back focal plane image scatterometry to address the challenges posed by high aspect ratio structures. Compared to FIB/SEM measurement results, our hybrid metrology measurement result achieves a measurement bias of less than 3% for all critical dimensions, demonstrating the system's capability for measuring high aspect ratio microstructures.

X-ray Photoemission Spectroscopy Techniques for Semiconductor Electronic Structure Analysis and Applications [ 下載 PDF ]

Cheng-Maw Cheng, Tzu-Hung Chuang, Pei-Yu Chuang

Based on the famous photoelectric effect proposed by Albert Einstein a century ago, various photoelectron spectroscopy techniques have developed and been widely applied to the analysis and characterization of the electronic structures of semiconductors. This article will introduce the principles of various X-ray photoelectron spectroscopy and microscopy techniques, as well as their applications in measuring the electronic structures of two-dimensional semiconductors and heterostructure interfaces. The spin properties of electrons and their analysis methods will also be discussed.

X-ray Scattering Techniques for Semiconductor Analysis and Applications [ 下載 PDF ]

Jhih-Min Lin, Shih-Chang Weng

X-ray scattering techniques encompass a variety of non-destructive analytical methods that are widely applied in the structural analysis of materials as well as the study of their physical and chemical properties. Commonly used techniques include X-ray diffraction (XRD), small- and wideangle X-ray scattering (SAXS/WAXS), X-ray reflectivity (XRR), X-ray Raman scattering (XRS), Compton scattering, and resonant/non-resonant inelastic X-ray scattering (RIXS/NRIXS). Based on the energy transfer characteristics during the scattering process, these techniques can be broadly classified into elastic scattering and inelastic scattering. This article focuses on the application of elastic X-ray scattering techniques in semiconductor testing, primarily targeting the microstructural analysis of materials. These techniques provide crucial information for characterizing nanoscale
structures, which is vital for semiconductor manufacturing processes.

In-situ Process Monitoring Technologies for Plasma and Non-plasma Processes [ 下載 PDF ]

Toru Shimizu

As semiconductor devices become more miniaturized with complicated process flow, in-situ process monitor technology is becoming more and more important. Especially, endpoint control technology in etching processes is one of key technologies at the most advanced process nodes. Optical emission spectroscopy (OES) is widely known as a monitoring tool for plasma dry etching. This article describes the OES technology and examples of its applications to actual processes. The latest process monitoring technology that does not rely on plasma emission but uses byproduct measurement in the exhaust line of the chamber is also introduced.

In-line NDIR Gas Monitor for Precursor and Impurity Monitoring [ 下載 PDF ]

Toru Shimizu

Precursor delivery by using carrier gases, called bubbling method, faces technical challenges on the production stability of CVD/ALD. An in-line NDIR (nondispersive infrared) gas monitor was designed to monitor a commercially available precursor and one of its impurities. The behaviors of the precursor and the impurity including the effect of idle time were observed for two different canisters. This article shows that monitoring precursors with in-line NDIR gas monitors may help to improve production yields by ensuring differences between canisters, the precursor status and the stabilization time before starting the process.

The in-situ Measuring Technologies Applied on Atomic Layer Deposition [ 下載 PDF ]

Chien-Wei Chen, Chan-Yuen Chang

This technology integrates an X-ray photoelectron spectrometer (XPS) with advanced process modules namely an atomic layer deposition (ALD) system, an atomic layer etching (ALE) system, and a rapid thermal processing (RTP) system and incorporates a self-developed wafer transfer system that enables vacuum transfer of chips between each module. In addition to the advantages of equipment automation, the primary objective is to minimize the chip’s exposure to the atmosphere while it is being transferred to the analysis chamber. By maintaining high-vacuum conditions, potential physical, chemical, or other forms of contamination from the external environment are eliminated, thereby obtaining data that closely represents the sample’s original state. Using this platform, we have successfully validated the development of low-oxygen ALD thin-film processes—an achievement that addresses the longstanding challenges faced by standalone ALD tools in depositing highly water- and oxygen-sensitive films. Moreover, processes such as film sulfidation, fluorination, annealing, and even plasma reduction can be precisely monitored in near-real time, yielding highly reliable chemical spectroscopic and compositional analysis results. Comparisons with conventional ex-situ methods consistently demonstrate that this approach can indeed overcome certain environmental influences and interferences, providing more accurate and representative data.

3D Plenoptic Imaging Technology for in-situ Inspection of Industrial Manufacturing Processes [ 下載 PDF ]

Chih-Hao Lin, Ming-Fu Chen, Yi-Hao Lin

Light field contains planar positions and directions of light, which can record and reconstruct 3D shape of targets. Architecture of plenoptic imaging systems, design principals of optical systems, and methods of depth estimation and 3D image reconstruction are introduced. Compared with popular 3D optical inspection technologies, plenoptic imaging technologies are relatively simple, economical, and fast. However, estimated depths are inaccurate in certain lighting environments. Experimental results of PCIE PINs show that estimated depths are noisy with nonuniform lighting. A simulation environment is built from a plenoptic imaging system add-on of Blender to simulate depth estimation with various lighting environments. Reflected images of general light sources from surfaces of targets significantly decrease accuracy of estimated depths of targets. When light sources are imaged on surfaces of targets, interference of light sources is reduced. A lighting system including a ring light module and a coaxial light is proposed. The coaxial light uses a uniform planar light source rather than a point light source, and is imaged on surfaces of targets by the first group of the main lens, which avoids interference on depth detection and mechanical interference with the main lens. The ring light illuminates inclined structures on surfaces of targets, and objects with side wall structures can be measured clearly. Nevertheless, to measure characteristic scale or detect defects accurately, a customized light source according to feature of targets is necessary, especially for detecting defects in 3D semiconductor packaging.

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Real-time Signal Compensation Feedback Control for Linear Motor Stage Using Fabry-Pérot Laser Interferometer [ 下載 PDF ]

Yi-Cheng Lin, Yi-Kai Tseng

As the size of semiconductor wafers continues to increase, the demand for high-precision, large-range motion control has also significantly risen. This paper utilizes the IDS3010 laser interferometer produced by the German company attocube for real-time signal compensation feedback control of a linear motor stage. The IDS3010 is a high-precision displacement measurement device based on the Fabry-Pérot interferometer principle. It uses the first reflection occurring within the sensor head and the second reflection from the target retroreflector to form an interference cavity. The phase difference generated by multiple reflections of the laser light due to the movement of the target is used to calculate the displacement. In terms of real-time compensation, the IDS3010 has the function of real-time output of measurement data, offering five output formats: HSSL, AquadB, Sin-Cosine, Linear Analog, and Biss-C, which can be selected as needed. It can be matched with commercial servo motor drivers and has a data output frequency of up to 25 MHz, providing sub-nanometer resolution and stable measurement data over a very high dynamic range. Compared to incremental encoder installed on stages, experimental results show that using the IDS3010 laser interferometer as a real-time compensation feedback signal source can significantly improve the repeatability and accuracy of the stage`s positioning, which is crucial for precise positioning in semiconductor processes.