• 전기학회논문지
• /
• 제60권7호
• /
• pp.1434-1437
• /
• 2011

Precision measurement of silicon wafer resistivity has been using single-configuration Four-Point Probe(FPP) method. This FPP method have to applying sample size, shape and thickness correction factor for a probe pin spacing to precision measurement of silicon wafer. The deference for resistivity measurement values applied correction factor and not applied correction factor was about 1.0 % deviation. The sample size, shape and thickness correction factor for a probe pin spacing have an effects on precision measurement for resistivity of silicon wafer.

• 한국전자파학회논문지
• /
• 제30권2호
• /
• pp.111-123
• /
• 2019

본 논문에서는 온-웨이퍼형 DUT 측정을 위한 입력 터미네이션의 정의방법을 제안하였으며, 제안된 방법으로 새롭게 정의된 입력 터미네이션과 잡음전력비에 기초한 잡음상관행렬 측정방법을 이용, 온-웨이퍼형 DUT의 잡음상관행렬을 측정하였다. 그리고 온-웨이퍼 DUT를 측정하기 위해 웨이퍼 프로브와 바이어스-티가 포함된 잡음측정 구성을 보였다. 온-웨이퍼형 DUT 측정을 위한 입력 터미네이션을 정의하기 위해서는 바이어스-티와 프로브 그리고 open으로 종단된 선로가 결합된 어댑터의 S-파라미터가 필요하며, 이를 위해 1-포트 측정을 통해 어댑터의 2-포트 S-파라미터를 결정하는 방법을 보였다. 이 측정된 어댑터의 S-파라미터 이용, 온-웨이퍼형 DUT 측정을 위한 새로운 입력 터미네이션을 정의하는 방법을 보였다. 제안된 방법으로 1.5 dB의 잡음지수를 갖는 칩 소자의 잡음상관행렬을 측정하였고, 측정된 잡음상관행렬을 이용하여 칩 소자의 잡음 파라미터 결과를 얻었다. 칩 소자의 잡음 파라미터 결과는 칩 소자의 데이터시트에 있는 잡음 파라미터 결과와 유사한 결과를 보였으며, 반복 측정을 통해 측정된 결과가 신뢰할 수 있는 결과임을 보였다.

• 반도체디스플레이기술학회지
• /
• 제2권2호
• /
• pp.9-15
• /
• 2003

This paper proposes a thickness measurement method of silicon-oxide and poly-silicon film deposited on 12" silicon wafer for spin etcher. Halogen lamp is used as a light source for generating a wide-band spectrum, which is guided and focused on the wafer surface through a optical fiber cable. Interference signal from the film is detected by optical sensor to determine the thickness of the film using spectrum analysis and several signal processing techniques including curve-fitting and adaptive filtering. Test wafers with three kinds of priori-known films, polysilicon(300 nm), silicon-oxide(500 nm) and silicon-oxide(600 nm), are measured while the wafer is spinning at 20 Hz and DI water flowing on the wafer surface. From experiment results the algorithm presented in the paper is proved to be effective with accuracy of maximum 0.8% error.rror.

• 한국정밀공학회지
• /
• 제17권1호
• /
• pp.129-137
• /
• 2000

In this paper, a new method of noncontact measurement has been developed for a 3 dimensional topography in semiconductor wafer, implementing a new optical probe based on the precision defocus measurement. The developed technique consists of the new optical probe, precision stages, and the measurement/control system. The basic principle of the technique is to use the reflected slit beam from the specimen surface, and to measure the deviation of the specimen surface. The defocusing distance can be measured by the reflected slit beam, where the defocused image is measured by the proposed optical probe, giving very high resolution. The distance measuring formula has been proposed for the developed probe, using the laws of geometric optics. The precision calibration technique has been applied, giving about 10 nanometer resolution and 72 nanometer of four sigma uncertainty. In order to quantitize the micro pattern in the specimen surface, some efficient analysis algorithms have been developed to analyse the 3D topography pattern and some parameters of the surface. The developed system has been successfully applied to measure the wafer surface, demonstrating the line scanning feature and excellent 3 dimensional measurement capability.

• 반도체디스플레이기술학회지
• /
• 제12권4호
• /
• pp.39-44
• /
• 2013

In the semiconductor heat-treatment process, the temperature uniformity determines the film quality of a wafer. This film quality effects on the overall yield rate. The heat transfer of the wafer surface in the heat-treatment process equipment is occurred by convection and radiation complexly. Because of this, there is the nonlinearity between the wafer temperature and reactor. Therefore, the accurate prediction of temperature on the wafer surface is difficult without the direct measurement. The thermal camera and the T/C wafer are general ways to confirm the temperature uniformity on the heat-treatment process. As above ways have limit to measure the temperature in the precise domain under the micro-scale. In this study, we developed the thin film type temperature sensor using the MEMS technology to establish the system which can measure the temperature under the micro-scale. We combined the experiment and numerical analysis to verify and calibrate the system. Finally, we measured the temperature on the wafer surface on the semiconductor process using the developed system, and confirmed the temperature variation by comparison with the commercial T/C wafer.

• 반도체디스플레이기술학회지
• /
• 제17권4호
• /
• pp.86-90
• /
• 2018

Standards related to express the non-flatness of a wafer are reviewed and discussed, for example, bow, warp, and sori. Novel wafer warpage measurement method is proposed for 3D stacked IC application. The new way measures heat transfer from a heater to a wafer, which is a function of the contact area between these two surfaces and in turn, this contact area depends on the wafer warpage. Measurement options such as heating from room temperature and cooling from high temperature were experimentally examined. The heating method was found to be sensitive to environmental conditions. The cooling technique showed more robust and repeatable results and the further investigation for the optimal cooling condition is underway.

• 한국기계가공학회지
• /
• 제13권6호
• /
• pp.139-144
• /
• 2014

As a result of a mismatch of the residual stress between both sides of the silicon wafer, which warps and distorts during the patterning process. The accuracy of the warpage measurement is related to the calibration. A CCD camera was used for the calibration. Performing optimization of the error function constructed with phase values measured at each pixel on the CCD camera, the coordinates of each light source can be precisely determined. Measurement results after calibration was performed to determine the warpage of the silicon wafer demonstrate that the maximum discrepancy is $5.6{\mu}m$ with a standard deviation of $1.5{\mu}m$ in comparison with the test results obtained by using a Form TalySurf instrument.

• 센서학회지
• /
• 제27권5호
• /
• pp.300-305
• /
• 2018

The uncooled microbolometer thermal sensor for low cost and mass volume was designed to target the new infrared market that includes smart device, automotive, energy management, and so on. The microbolometer sensor features 80x60 pixels low-resolution format and enables the use of wafer-level vacuum packaging (WLVP) technology. Read-out IC (ROIC) implements infrared signal detection and offset correction for fixed pattern noise (FPN) using an internal digital to analog convertor (DAC) value control function. A reliable WLVP thermal sensor was obtained with the design of lid wafer, the formation of Au80%wtSn20% eutectic solder, outgassing control and wafer to wafer bonding condition. The measurement of thermal conductance enables us to inspect the internal atmosphere condition of WLVP microbolometer sensor. The difference between the measurement value and design one is $3.6{\times}10-9$ [W/K] which indicates that thermal loss is mainly on account of floating legs. The mean time to failure (MTTF) of a WLVP thermal sensor is estimated to be about 10.2 years with a confidence level of 95 %. Reliability tests such as high temperature/low temperature, bump, vibration, etc. were also conducted. Devices were found to work properly after accelerated stress tests. A thermal camera with visible camera was developed. The thermal camera is available for non-contact temperature measurement providing an image that merged the thermal image and the visible image.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2005년도 추계종합학술대회
• /
• pp.861-864
• /
• 2005

Performing accurate and repeatable low frequency noise measurement is critical for modeling and simulation of flicker noise. Through the accurate and repeatable on-wafer measurement, low frequency noise characteristics of the 0.18 ${\mu}m$ n-MOSFETs are discussed. And on-wafer flicker noise measurement system is presented. The on-wafer measurement system consists of cascade probe station, low noise current amplifier (SR570), and dynamic signal analyzer (HP35670A).

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
• /
• pp.223.1-223.1
• /
• 2013

Since sapphire single crystal is one of the materials that have excellent mechanical and optical properties, the single crystal is widely used in various fields, and the demand for the use of substrate of LED devices is increasing rapidly. However, crystal defects such as dislocations and stacking faults worsen the properties of the single crystal intensely. When sapphire wafer of single crystal is used as LED substrate, especially, crystal defects have a strong influence on the characteristics of a film deposited on the wafer. In such a case quantitative assessment of the defects is essential, and the evaluation technique is now becoming one of the most important factors in commercialization of sapphire wafer. Wet etching is comparatively easy and accurate method to estimate dislocation density of single crystal because etching reaction primarily takes place where dislocations reached crystal surface which are chemically weak points, and produces etch pit. In the present study, the formation behavior of etch pits and etching time dependence were studied systematically. Etch pit density(EPD) analysis using optical microscope was also conducted and measurement uncertainty of EPD was studied to confirm the reliability of the results. EPDs and measurement uncertainties for 4 inch sapphire wafers were analyzed in terms of 5 and 21 points EPD readings. EPDs and measurement uncertainties in terms of 5 points readings for 4 inch wafers were compared by 2 organizations. We found that the average EPD value in terms of 5 points readings for a 4 inch sapphire wafer may represent the EPD value of the wafer.