• Korean Journal of Optics and Photonics
• /
• v.7 no.2
• /
• pp.101-111
• /
• 1996

Optical microscopes integrated with CCD cameras are widely used for automatic inspection of precision circuit patterns fabricated on glass masks and silicon wafers. For this application it is important to position the object always is focus so that the image appears in good quality while the microscope scans the object. However, as the magnification of the microscope is taken large for fine resolution the depth of focus becomes small, often in submicron ranges, requiring special care in focusing. This study proposes a new auto-focusing method, which can be readily incorporated in existing optical configuration of microscope. This method is based on optical triangulation using a separate beam of laser and two photodiodes, eliminating focus errors caused by surface roughness and waviness. Experimental results prove that the method can produce focus error signals which are very sensitive with a resolution of 5 nm within 0.5 ${\mu}{\textrm}{m}$ accuracy.

• Proceedings of the Optical Society of Korea Conference
• /
• 1996.09a
• /
• pp.82-82
• /
• 1996

• Proceedings of the Optical Society of Korea Conference
• /
• 2005.07a
• /
• pp.172-173
• /
• 2005

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.103.5-103
• /
• 2001

This paper presents a visual feedback system that controls a micromanipulator using multiple microscopic vision information. The micromanipulation stations basically have optical microscope. However the single field-of-view of optical microscope essentially limits the workspace of the micromanipulator and low dept-of-field makes it difficult to handle 3D-shaped micro objects. The system consists of a stereoscopic microscope, three CCD cameras, the micromanipulator and personal computer. The use of stereoscopic microscope which has long working distance and high depth-of-field with selective field-of-view improves the recognizability of 3D-shaped micro objects and provides a method for overcoming several essential limitations in micromanipulation. Thus, visual feedback information is very important in handling micro objects for overcoming those limitations and provides a mean for the ...

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.35S no.3
• /
• pp.120-130
• /
• 1998

In this study, we implemented a scanning capacitance decimicron micorscope(SCdM) which scans a surface of the object mechanically in two or two point five dimensions with a stylus of size 0.2.mu.m. X-Y stage and stylus driving method are used as the scanning method, and VHD disk plate and IC chip are used as the object. Experimenal resutl of these object show that SCdM obtain 0.1.mu.m resolution power which exceeds that of optical microscope, and this microscope will be used as a powerful tool for inspecting ULSI pattern or biological data as a decimicron mcirocope which zoom a function of optical microscope and guide STM. The experimental system is composed of a VHD video disk method which captures the capacitance changes of the video disk suface and converts it into video signal.

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.367-368
• /
• 2007

Dissection of rat hippocampus using high-definition stereoscopic microscope system is demonstrated. Many surgical operation or animal anatomies are anatomized with stereoscopic microscope. With stereoscopic microscope system, the environments of operation is important factor to dissector. Lights, resolution of acquired stereo images, reflected on the liquid, colors and eye fatigue are fatal factors to dissector. We reduced reflections with two incident angle of lights at 45 degree and used a complementary color at the basement and reform the stereoscopic microsystem. Dissector has felt more comfortable after compensation and operation time is more continuous.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.12 no.1
• /
• pp.27-34
• /
• 1999

We investigated the effect of mechanical back side damage in viewpoint of electrical and surface morphological characteristics in Czochralski silicon wafer. The intensity of mechanical damage was evaluated by minority carrier recombination lifetime by laser excitation/microwave reflection photoconductance decay technique, atomic force microscope, optical microscope, wet oxidation/preferential etching methods. The data indicate that the higher the mechanical damage degree, the lower the minority carrier lifetime, and surface roughness, damage depth and density of oxidation induced stacking fault increased proportionally.

• Journal of the Korean Society for Precision Engineering
• /
• v.26 no.8
• /
• pp.72-78
• /
• 2009

We developed a line standards measurement system using an optical microscope and measured two kinds of line standards. It consists of three main parts: an optical microscope module including a CCD camera, a stage system with a linear encoder, and a measurement program for a microscopic image processing. The magnification of microscope part was calibrated using one-dimensional gratings and the angular motion of stage was measured to estimate the Abbe error. The threshold level in line width measurement was determined by comparing with certified values of a line width reference specimen, and its validity was proved through the measurement of another line width specimen. The expanded uncertainty (k=2) was about 100 nm in the measurements of $1{\mu}m{\sim}10{\mu}m$ line width. In the comparison results of line spacing measurement, two kinds of values were coincide within the expanded uncertainty, which were obtained by the one-dimensional measuring machine in KRISS and the line standards measurement system. The expanded uncertainty (k=2) in the line spacing measurement was estimated as $\sqrt{(0.098{\mu}m)^2+(1.8{\times}10^{-4}{\times}L)^2}$. Therefore, it will be applied effectively to the calibration of line standards, such as line width and line spacing, with the expanded uncertainty of several hundreds nanometer.

• Proceedings of the Optical Society of Korea Conference
• /
• 1996.09a
• /
• pp.81-81
• /
• 1996

• Proceedings of the Optical Society of Korea Conference
• /
• 2004.02a
• /
• pp.58-59
• /
• 2004