• Journal of the Optical Society of Korea
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• 제18권3호
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• pp.236-243
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• 2014

Surface profiling and film thickness measurement play an important role for inspection. White light interferometry is widely used for engineering surfaces profiling, but its applications are limited primarily to opaque surfaces with relatively simple optical reflection behavior. The conventional bucket algorithm had given inaccurate surface profiles because of the phase error that occurs when a thin-film exists on the top of the surface. Recently, reflectometry and white light scanning interferometry were combined to measure the film thickness and surface profile. These techniques, however, have found that many local minima exist, so it is necessary to make proper initial guesses to reach the global minimum quickly. In this paper we propose combing reflectometry and white light scanning interferometry to measure the thin-film thickness and surface profile. The key idea is to divide the measurement into two states; reflectometry mode and interferometry mode to obtain the thickness and profile separately. Interferogram modeling, which considers transparent thin-film, was proposed to determine parameters such as height and thickness. With the proposed method, the ambiguity in determining the thickness and the surface has been eliminated. Standard thickness specimens were measured using the proposed method. Multi-layered film measurement results were compared with AFM measurement results. The comparison showed that surface profile and thin-film thickness can be measured successfully through the proposed method.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.565-568
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• 2005

We describe a new scheme of dispersive white-light interferometer that is capable of measuring the thickness profile of thin-film layers, for which not only the top surface height profile but also the film thickness of the target surface should be measured at the same time. The interferometer is found useful particularly for in-situ inspection of micro-engineered surfaces such as liquid crystal displays, which requires for high-speed implementation of 3-D surface metrology.

• 한국광학회지
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• 제10권5호
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• pp.373-378
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• 1999

투명한 유전체 박막과 관련된 측정 분야는 반도체 산업의 발전과 함께 급속히 성장하고 있으며, 회로의 고집적화 추세에 맞추어 고정밀도의 측정 성능을 요구하고 있다. 최근 웨이퍼의 광역 평탄화를 위한 CMP(chemical mechanical polishing)공정의 도입으로 인하여 박막의 두께뿐만 아니라 미세 형상에 대한 측정 요구가 증가하고 있다. 이 논문에서는 기존의 비접촉 표면 형상 측정법의 하나인 백색광 주사 간섭법을 이용하여 박막의 두께 형상을 측정하여 새로운 측정 알고리즘 제시하고자 한다. 이 방법은 기존의 백색광 간섭 신호 해석법의 하나인 주파수 분석법과 비선형 최소 자승법을 이용함으로써 구현된다. 그리고 실험을 통하여 개발된 알고리즘의 타당성을 검증한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2533-2535
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• 1998

In this paper, an effect of drive-in process temperature on the residual stress profile of the p+ silicon film has been investigated. The residual stress profile has been calculated as the fourth-order polynomials. All coefficients of the polynomials have been determined from the measurement of the vertical deflections of the p+ silicon cantilevers with various thickness and the tip displacement of the p+ silicon rotating beam. From the determination results of the residual stress profile, the average stress of the film thermally oxidized at 1000 $^{\circ}C$ is 15 MPa and that of the film oxidized at 1100 $^{\circ}C$ is 25 MPa. The profile of the residual stress through the high temperature drive-in process has a steeper gradient than the other case.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.289.1-289.1
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• 2016

Germanium (Ge) with higher carrier mobility and a lower crystallization temperature has been considered as the channel material of thin-film transistors for display applications. Various methods were studied for crystallizaion of poly-Ge from amorphous Ge at low temperature. Especially Metal induced crystalliazation (MIC) process was widely studied because low process cost. In this paper, we investigate copper diffusion process of different thick (70 nm, 350 nm) poly-Ge film obtained by MIC process at various temperatures (250, 300, and $350^{\circ}C$) through atomic force microscopy (AFM), Raman spectroscopy, and secondary ion mass spectroscopy (SIMS) measurement. Crystallization completeness and grain size was similar in all the conditions. Copper diffusion profile of 370 nm poly-Ge film show simirly results regardless of process temperature. However, copper diffusion profile of 70 nm poly-Ge film show different results by process temperature.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.86-87
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• 2007

The dispersive method of white-light interferometry is proper for in-line 3-D inspection of dielectric thin-film thickness to be used in the semiconductor and flat-panel display industry. This research is the measurement application of CMP patterned wafer. The results describe 3-D and 2-D profile of the step height during polishing time.

• 한국정밀공학회지
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• 제21권6호
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• pp.15-21
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• 2004

반도체 제조산업과 나노, 바이오 산업의 비약적 발전에 따라 게이트 산화막(gate oxide)과 같이 반도체 제조공정에서 사용되는 유전체 박막(dielectric film)의 두께는 수 $\mu\textrm{m}$에서 수 nm 에 이르기까지 다양할 뿐 아니라 얇아지고 있으며, 또한 이러한 박막들이 다층으로 복잡하게 적층된 다층 박막의 응용이 높아지는 추세이다. 따라서, 반도체 및 광통신 소자, 발광소자, 바이오 칩 어레이 등과 같은 나노박막을 이용하는 산업에서는 박막의 두께 측정을 더욱 정확하고, 보다 빠르며 효율적으로 측정할 수 있는 박막 두께 측정용 계측기가 요구된다.(중략)

• 한국재료학회지
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• 제20권8호
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• pp.434-438
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• 2010

The selenization process has been a promising method for low-cost and large-scale production of high quality CIGS film. However, there is the problem that most Ga in the CIGS film segregates near the Mo back contact. So the solar cell behaves like a $CuInSe_2$ and lacks the increased open-circuit voltage. In this study we investigated the Ga distribution in CIGS films by using the $Ga_2Se_3$ layer. The $Ga_2Se_3$ layer was applied on the Cu-In-Ga metal layer to increase Ga content at the surface of CIGS films and to restrict Ga diffusion to the CIGS/Mo interface with Ga and Se bonding. The layer made by thermal evaporation was showed to an amorphous $Ga_2Se_3$ layer in the result of AES depth profile, XPS and XRD measurement. As the thickness of $Ga_2Se_3$ layer increased, a small-grained CIGS film was developed and phase seperation was showed using SEM and XRD respectively. Ga distributions in CIGS films were investigated by means of AES depth profile. As a result, the [Ga]/[In+Ga] ratio was 0.2 at the surface and 0.5 near the CIGS/Mo interface when the $Ga_2Se_3$ thickness was 220 nm, suggesting that the $Ga_2Se_3$ layer on the top of metal layer is one of the possible methods for Ga redistribution and open circuit voltage increase.

• 한국자기학회지
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• 제19권2호
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• pp.47-51
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• 2009

유리판 위에 증착된 다결정 Fe 자성박막의 두께에 따른 표면 결정 구조가 Ti : Sapphire 레이저를 사용하여 조사되었다. 비선형 광학 유전율의 결정구조에 따른 대칭성에 대한 계산으로부터 박막 표면은 $C_{2v}$에 매우 가까운 $C_s$ 구조를 갖음을 보였다. 이러한 광학적 회전 이방성은 임의 방향의 그레인으로 구성된 다결정 구조의 박막에서는 매우 이례적인 일이다. 이차조화파로부터 얻은 이 결과는 (110) bcc 형태로 자란 X선 회절 결과와도 일치하는 것으로 매우 얇은 상태일 때 가지고 있던 박막 표면의 등방 구조가 두께가 증가함에 따라 바뀌면서 bulk 상태의 구조를 점차적으로 갖게 됨을 보여주고 있다.