• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.456-456
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• 2009

Boron doping on an n-type Si wafer is requisite process for IBC (Interdigitated Back Contact) solar cells. Fiber laser annealing is one of boron doping methods. For the boron doping, uniformly coated or deposited film is highly required. Plasma enhanced chemical vapor deposition (PECVD) method provides a uniform dopant film or layer which can facilitate doping. Because amorphous silicon layer absorption range for the wavelength of fiber laser does not match well for the direct annealing. In this study, to enhance thermal affection on the existing p-a-Si:H layer, a ${\mu}c$-Si:H intrinsic layer was deposited on the p-a-Si:H layer additionally by PECVD. To improve heat transfer rate to the amorphous silicon layer, and as heating both sides and protecting boron eliminating from the amorphous silicon layer. For p-a-Si:H layer with the ratio of $SiH_4$ : $B_2H_6$ : $H_2$ = 30 : 30 : 120, at $200^{\circ}C$, 50 W, 0.2 Torr for 30 minutes, and for ${\mu}c$-Si:H intrinsic layer, $SiH_4$ : $H_2$ = 10 : 300, at $200^{\circ}C$, 30 W, 0.5 Torr for 60 minutes, 2 cm $\times$ 2 cm size wafers were used. In consequence of comparing the results of lifetime measurement and sheet resistance relation, the laser condition set of 20 ~ 27 % of power, 150 ~ 160 kHz, 20 ~ 50 mm/s of marking speed, and $10\;{\sim}\;50 {\mu}m$ spacing with continuous wave mode of scanner lens showed the correlation between lifetime and sheet resistance as $100\;{\Omega}/sq$ and $11.8\;{\mu}s$ vs. $17\;{\Omega}/sq$ and $8.2\;{\mu}s$. Comparing to the singly deposited p-a-Si:H layer case, the additional ${\mu}c$-Si:H layer for doping resulted in no trade-offs, but showed slight improvement of both lifetime and sheet resistance, however sheet resistance might be confined by the additional intrinsic layer. This might come from the ineffective crystallization of amorphous silicon layer. For the additional layer case, lifetime and sheet resistance were measured as $84.8\;{\Omega}/sq$ and $11.09\;{\mu}s$ vs. $79.8\;{\Omega}/sq$ and $11.93\;{\mu}s$. The co-existence of $n^+$layeronthesamesurfaceandeliminating the laser damage should be taken into account for an IBC solar cell structure. Heavily doped uniform boron layer by fiber laser brings not only basic and essential conditions for the beginning step of IBC solar cell fabrication processes, but also the controllable doping concentration and depth that can be established according to the deposition conditions of layers.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.80-83
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• 2000

본 연구에서는 유기물 전자소자 개발을 위한 기초 연구로서 증착시 기판의 온도, 증칙비, 열처리 온도에 따른 펜타신 박막의 수평방향 전기전도도, 접촉저항, 면저항 둥 전기적 특성을 측정 하였다. 시료는 분말형 펜타신을 유기분자선 성막장치(OMBD)를 이용하여 성막 하였다. 전도도 계산을 위한 두께의 측정은 $\alpha$-step을 이용하였으며, TLM(transfer length method)으로 접촉저항, 면저항등 전기적 특성을 측정하였다. 전극은 Au를 사용하여 진공 증착법으로 제작하였다. 기판의 온도는 3$0^{\circ}C$, 4$0^{\circ}C$, 5$0^{\circ}C$, 6$0^{\circ}C$, 7$0^{\circ}C$, 8$0^{\circ}C$, 10$0^{\circ}C$ 일곱 종류로 하여 증착비를 달리 하였고, 열처리에 의한 효과는 10$0^{\circ}C$에서 증착한 시료를 10$0^{\circ}C$, 14$0^{\circ}C$에서 각각 10초간 열처리를 실시하였다. 기판 온도에 따른 막의 형상은 AFM을 이용하여 관찰하였다. 기판의 온도가 상승할수록 박막의 결정화가 활발히 진행되었으며 최대단일결정은 4$\mu\textrm{m}$였다. 전기전도도는 7.40$\times$$10^{-7}$ S/cm ~ 0.778$\times$$10^{-5}$ S/cm의 값을 나타내었으며, 접족저항은 10$0^{\circ}C$에서 증착하고 14$0^{\circ}C$에서 10초간 열처리 한 경우 2.5324㏁으로 가장 작았으며, 면저항은 약간의 차이는 있으나 전체적으로 ≒ $10^{9}$ Ω/ 의 값을 보였다

• 한국전기전자재료학회논문지
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• 제21권4호
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• pp.362-367
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• 2008

We have Manufactured the low-k dielectric interlayer fabricated by plasma enhanced chemical vapor deposition (PECVD), The thin film of SiOCH is studied correlation between components and Dielectric constant. The precursor was evaporated and introduced with the flow rates from 16 sccm to 25 sccm by 1sccm step in the constant flow rate of 60 sccm $O_2$ in process chamber. The chemical characteristics of SiOCH were analyzed by measuring FT/IR absorption lines and obtained each dielectric constant measuring C-V. Then compare respectively. ILD of BTMSM/$O_2$ could have low dielectric constant about $k\sim2$, and react sensitively. Also dielectric constant could be decreased by the effects of decreasing $CH_3$ and growing Si-O-Si(C) after annealing process.

• 한국전기전자재료학회논문지
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• 제13권11호
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• pp.969-975
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• 2000

Laser direct writing of micro-patterned copper lines has been achieved by pyrolytic decomposition of copper formate films (Cu(HCOO)$_2$.4$H_2O$), as a metallo-organic precursor, using a focused CW Ar$^{+}$ laser beam (λ=514nm) on PCB boards and glass substrates. The linewidth and thickness of the lines wee investigated as a functin of laser power and scan speed. The profiles of the lines were measured by scanning electron microscope (SEM), surface profiler ($\alpha$-step) and atomic force measured by scanning electron microscope (SEM), surface profiler ($\alpha$-step) and atomic force microscopy (AFM). The electrical resistivities of the patterned lines were also investigated as a function of laser parameters using probe station and semiconductor analyzer. We compared resistivities of the patterned copper lines with these of the Cu bulk. Resistivities decreased due to changes in morphology and porosity of the deposit, which were about 3.8 $\mu$$\Omega$cm and 12$\mu$$\Omega$cm on PCB and glass substrates after annealing at 30$0^{\circ}C$ for 5 minutes.s.

• 한국전기전자재료학회논문지
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• 제11권9호
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• pp.739-745
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• 1998

The objective of this paper is to provide experimental data of Er(rare- earth)doped $SiO_2$thin film made by sputtering methods. The deposition rate of silica glass by sputtering method was 55$\AA$/min. In EDD measurements, the average Er concentration in the deposited film was 0.77(wt%). After annealing at $900^{\circ}C$, the Cl concentration decreased from 3.79(wt%) to 1.52(wt%). The refractive indices of the core $n_1$, cladding $n_2$ were 1.458, 1.558 respectively at 632.8 nm. The refractive index difference between core and cladding, $\Delta$n was 0.1. The refractive index profile of core and cladding interface shows step profile. In the study, $SiO_2$ glass films of Si wafer were successfully doped with active erbium. Therefore, this experimental data will be applicable for fabrications of Er doped planar integrated optical device.

• Journal of Magnetics
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• 제20권3호
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• pp.211-214
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• 2015

$Cr_2O_3$ nanoparticles were prepared via one-step reactive laser ablation of Cr in oxygen. The metastable $CrO_2$ phase was obtained through the subsequent oxidation of $Cr_2O_3$ nanoparticles under $O_2$ with gas pressures of up to 40 MPa. The as-prepared $Cr_2O_3$ nanoparticles are spherical or rectangular in shape with sizes ranging from 20 nm to 50 nm. High oxygen pressure annealing is effective in producing meta-stable $CrO_2$ from as-dried $Cr_2O_3$ nanoparticles, and the $Cr_2O_3$ nanoparticles exhibit a weak ferromagnetic behavior with an exchange bias of up to 11 mT that can be ascribed to the interfacial exchange coupling between uncompensated surface spins and the antiferromagnetic core. The $Cr_2O_3/CrO_2$ nanoparticles exhibit an enhanced saturation magnetization and a reduced exchange bias with an increasing faction of $CrO_2$ due to the elimination of uncompensated surface spins over the $Cr_2O_3$ nanoparticles when exposed to a high pressure of $O_2$ and/or possible phase segregation that results in a smaller grain size for both $Cr_2O_3$ and $CrO_2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.170-173
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• 2001

Thin films of phase-pure perovskite (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) were deposited in-situ onto Pt/Ti/ $SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. Two-step process to grow (P $b_{0.72}$L $a_{0.28}$) $Ti_{0.93}$ $O_3$(PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Electrical properties including dielectric constant, ferroelectric characteristics, crystallization and leakage current of PLT thin films were shown to be strongly inf1uenced by grain size. Also PLT thin films on p-type(100) Si substrate will be fabricated by pulsed laser deposition technique using a Nd:YAG laser with different wavelengths of 355, 532 and 1064 nm. Effect of the variation of laser wavelength on dielectric properties will be discussed. Microstructural and electrical properties of the film were investigated by C-V measurement leakage current measurement and SEM.ent and SEM.

• 한국진공학회지
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• 제13권3호
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• pp.120-126
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• 2004

트렌치 소자 제조시 게이트 산화막 성장과 내압 강하의 원인이 되는 식각손상 회복과 코너 영역의 구조를 개선하기 위해 수소 분위기 열처리를 하였다. 열처리시 수소 원자에 의한 환원 반응을 이용하여 표면 에너지가 높은 코너 영역에서는 원자들의 이동에 의한 결정면 재배열, 산화막 측벽에서의 실리콘 원자 적층, 표면 거칠기의 개선 효과 등을 전자현미경 관찰을 통해 확인하였다. 실리콘 원자의 이동을 방해하는 식각 후 잔류 산화막을 수소 가스의 환원성 분위기에서 열처리함으로써 표면 에너지를 낮추는 방향으로 원자의 이동이 일어나 concave 영역, 즉 트렌치 bottom corner에서는 (111), (311) 결정면 재분포 현상이 일어남을 확인할 수 있었다. 또한 convex comer에서의 원자 이동으로 인해 corner 영역에서는 (1111) 면의 step 들이 존재하게 되고 원자 이동에 의해 산화막 측벽에 이르러 이동된 원자의 적층이 일어나며, 이는 열처리시 표면 손상 회복이 원자이동에 의함을 나타낸다. 이러한 적층은 표면 상태가 깨끗할수록 정합성을 띄어 기판과 일치하는 에피 특성을 나타내고 열처리 온도가 높을수록 표면 세정 효과가 커져 식각손상 회복효과가 커지며, 이를 이용하여 이후의 산화막 성장시 균일한 두께를 코너영역에서 얻을 수 있었다

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권9호
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• pp.623-627
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• 1999

We report a new in-situ fluorine passivation method without in implantation by employing excimer laser annealing of $SiO_{x}F_{y}$/a-Si structure and its effects on p-channel poly-Si TFTs. The proposed method doesn't require any additional annealing step and is a low temperature process because fluorine passivation is simultaneous with excimer-laser-induced crystallization. A in-situ fluorine passivation by the proposed method was verified form XPS analysis and conductivity measurement. From experimental results, it has been shown that the proposed method is effective to improve the electrical characteristics, specially field-effect mobility, and the electrical stability of p-channel poly-Si TFTs. The improvement id due to fluorine passivation, which reduces the trap state density and forms the strong Si-F bonds in poly-Si channel and $SiO_2/poly-Si$ interface. From these results, the high performance poly-Si TFTs canbe obtained by employing the excimer-laser-induced fluorine passivation method.

• Applied Science and Convergence Technology
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• 제27권5호
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• pp.105-108
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• 2018

Transparent $TiO_2$ nanotube arrays are successfully prepared by a two-step approach involving electrochemical anodization and RF magnetron sputtering. First, a Ti film is deposited on an FTO substrate by RF magnetron sputtering at room temperature. The morphologies of the Ti film are controlled by the working distance, Ar flow, and DC power. Second, an anodization treatment is electrochemically performed for the formation of nanotube arrays from the deposited Ti film, followed by post-annealing treatment in air for the formation of $TiO_2$ crystallization. The back side of the crystallized $TiO_2$ nanotube arrays is illuminated with solar light to characterize the photoelectrochemical reaction, and their photoelectrochemical properties are investigated. This work provides information on application of a thin film deposited by RF sputtering in the field of photoelectrochemical water splitting.