• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.2
• /
• pp.69-74
• /
• 2020

In this study, we proposed a method for surface profiling aspheric lens molds using a precision displacement sensor with a spatial scanning mechanism. The precision displacement sensor is based on the confocal principle using a broadband light source, providing a 10 nm resolution over a 0.3 mm measurable range. The precision of the sensor, depending on surface slope, was evaluated via Allan deviation analysis. We then developed an automatic surface profiling system by measuring the cross-sectional profile of a lens mold. The precision of the sensor at the flat surface was 10 nm at 10 ms averaging time, while 200 ms averaging time was needed for identical precision at the steepest slope at 25 deg. When we compared the measurement result of the lens mold to a commercial surface profiler, we found that the accuracy of the developed system was less than 90 nm (in terms of 3 sigmas of error) between the two results.

• Journal of the Korean Vacuum Society
• /
• v.12 no.3
• /
• pp.162-167
• /
• 2003

To find the concentration according to the depth-direction of ions implanted in the sample, with sputtering of the sample surface, one needs the depth profiling of ion implanted in the sample. On measuring of depth profiling, the sputtering rate to affect depth direction, is calculated by SRIM simulation. When ion is implanted in the sample, the atomic density of the sample rises up a little, and it alters sputtering yield. This alteration then causes differences of sputtering rate to affect depth-direction, on measuring of depth profiling. With the usage of SRIM Monte Carlo simulation code, one calculates sputtering rate, with sputtering yield by the alteration of atomic density of the sample through ion implantation. As a result, it goes to prove that its difference affects depth distribution, on measuring of depth profiling.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.13 no.1
• /
• pp.19-23
• /
• 2003

Polished surface of $CsB_{3}O_{5}$ (CBO) has been observed by reflection high energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS). For comparison, electronic properties of CBO powder have been studied by XPS. It has been found that the crystal surface is covered by thick amorphous layer with chemical composition closely related to that of CBO. Great enrichment of top surface by cesium, ~30 % in reference to the bulk of the modified layer, has been displayed by depth profiling.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1998.02a
• /
• pp.129-129
• /
• 1998

Most of the surface/interface analysis tools have limited depth profiling c capability in terms of the profiling range and the depth resolution. However, M MEIS can profile the surface and subsurface composition and structure q quantitatively and non-destructively with atomic layer depth resolution. I In this presentation, the MEIS system developed at KRISS will be briefly d described with an introduction on the principle of MEIS. Recent MEIS r results on the surface and interface composition and structural change due to i ion bombardment will be presented for preferential sputtering of T:없Os and d damage depth profiles of SHooD, Pt(l11), and Cu(l1D due to Ar+ ion b bombardment. Direct observation of strained Si lattices and its distribution i in the SHool)-SiCh interface and the initial stage of Co growth on Pt(l11) w will be reported. H surfactant effects on epitaxial growth of Ge on Si(ooD w will be discussed with STM results from SND.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1998.02a
• /
• pp.20-20
• /
• 1998

I Ion beam technology has recently attracted much interest because it has exciting t technological p아:ential for surface analysis, ion beam mixing, surface cleaning and etching i in thin film growth and semiconductor fabrication processes, etc. Es야~cially, ion beam s sputtering has been widely used for sputter depth profiling with x-photoelectron S spectroscopy (XPS) , Auger electron s$\pi$~troscopy(AES), and secondary-ion mass S야i따oscopy(SIMS). However, The problem of surface compositional ch없1ge due to ion b bombardment remains to be understo여 없ld solved. So far sputtering processes have been s studied by s따face an외ysis tools such as XPS, AES, and SIMS which use the sputtering p process again. It would be improbable to measure the modified surface composition profiles a accurately due to ion beam bombardment with surface analysis techniques based on sputter d depth profiling. However, recently Medium energy ion scattering spectroscopy(MEIS) has b been applied to study the sputtering of solid surface at ion bombardment and has been p proved that it has been extremely valuable in probing the surface composition 뻐d s structure nondestructively and quantita디vely with less than 1.0 nm depth resolution. To u understand the sputtering processes of solid surface at ion bombardment, The Molecular D Dynamics(MD) and Monte Carlo(MC) simulation has been used and give an intimate i insight into the sputtering processes of solid surfaces. In this presentation, the sputtering processes of alloys and compound samples at ion b bombardment will be reviewed and the MEIS results for the Ar+ sputter induced altered l layer of the TazOs thin film 뻐dd없nage profiling of Ar+ ion sputt얹"ed Si(100) surface will b be discussed with the results of MD and MC simulation.tion.

• Journal of the Korean Vacuum Society
• /
• v.8 no.3B
• /
• pp.283-289
• /
• 1999

Multilayer thin film reference materials for the sputter depth profiling analysis are used to calibrate the sputter depth scale by measuring the sputtering rate and to optimize the sputtering conditions for the best depth resolution. Surface analysis group of Korea Research Institute of Standards and science (KRISS) have developed various types of multilayer thin films by using an ion beam sputter deposition and in-situ surface analysis system. The chemical states of the thin films reference materials were certified by in-situ XPS and the thicknesses were certified by transmission electron microscopy (TEM).

• Korean Journal of Optics and Photonics
• /
• v.10 no.3
• /
• pp.201-207
• /
• 1999

The fiber-optical confocal scanning interference microscope with a simple configuration was constructed with a 4-port fiber-optic coupler, and the new method based on the phase shifting method was proposed for surface profiling by the system. In the method, the height of a specimen was determined from the phase of confocal beam. It was verified experimentally that the method was applicable to even the confocal interference microscope with a long-wavelength source and a low NA objective, and that the scanning time could be drastically reduced compared with the conventional method. Finally, it was found that our method is less sensitive to the variation of surface reflectivity than the conventional method.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.03a
• /
• pp.338-345
• /
• 2005

Recently, surface-wave methods have been widely used for site investigation due to economic advantage and improved reliability. Specially, the Spectral-Analysis-of-Surface-Wave (SASW) method has been used to evaluate soil properties in geotechnical engineering. In determination of subgrade stiffness by SASW measurements, only the vertical Rayleigh waves have been used. This study proposed a framework to determine shear-wave velocity profiles by using vertical and horizontal Rayleigh waves and Love wave all together. In addition, the Common-Array-Profiling(CAP) SASW method was employed, which subgrade stiffness of profile the local material under two fixed receivers. The procedure proposed in this study was verified by comparing the shear-wave velocity profiles with the shear-wave velocity profiles of downhole testing at two geotechnical sites.

• Journal of the Korean Vacuum Society
• /
• v.12 no.S1
• /
• pp.92-94
• /
• 2003

The sputtering yield change of an amorphous Si layer on Si(100) was measured quantitatively for 0.5 keV $O_2^{+}$ and $Ar^{+}$ ion bombardment with in suit MEIS. In the case of 0.5 keV $O_2^{+}$ ion bombardment, at the initial stage of sputtering before surface oxidation, the sputtering yield of Si was 1.4 (Si atoms/$O_2^{+}$) and then decreased down to 0.06 at the ion dose of $3\times10^{16}O_2\;^{+}\textrm{/cm}^2$. In the case of 0.5 keV $Ar^{+}$ ion bombardment, the sputtering yield of Si for the surface normal incidence was 0.56 at the ion dose of 2.5 ${\times}$ 10$^{15}$ $Ar^{+}\textrm{cm}^2$, and rapidly saturated to 1.2 at dose of $7.5\times10^{15}Ar^+\textrm{cm}^2$. For the incidence angle of 80 from surface normal, the sputtering yield of Si was saturated to about 1.4 at the initial stage of sputtering. The surface transient effects, caused by change in sputtering yield at the initial stage of sputtering can be negligible when 0.5 keV $Ar^{+}$ ion at extremely grazing angle was used for sputter depth profiling.g.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2005.08a
• /
• pp.42-43
• /
• 2005