• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.429-429
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• 2012

To investigate the gettering effect of B-doped n-type monocrystalline silicon wafer, we made the p-n junction by diffusing boron into n-type monocrystalline Si substrate and then oxidized the boron doped n-type monocrystalline silicon wafer by in-situ wet and dry oxidation. After oxidation, the minority carrier lifetime was measured by using microwave photoconductance and the sheet resistance by 4-point probe, respectively. The junction depth was analyzed by Secondary Ion Mass Spectrometry (SIMS). Boron diffusion reduced the metal impurities in the bulk of silicon wafer and increased the minority carrier lifetime. In the case of wet oxidation, the sheet resistance value of ${\sim}46{\Omega}/{\Box}$ was obtained at $900^{\circ}C$, depostion time 50 min, and drive-in time 10 min. Uniformity was ~7% at $925^{\circ}C$, deposition time 30 min, and drive-in time 10 min. Finally, the minority carrier lifetime was shown to be increased from $3.3{\mu}s$ for bare wafer to $21.6{\mu}s$ for $900^{\circ}C$, deposition 40 min, and drive-in 10 min condition. In the case of dry oxidation, for the condition of 50 min deposition, 10 min drive-in, and O2 flow of 2000 SCCM, the minority carrier lifetime of 16.3us, the sheet resistance of ${\sim}48{\Omega}/{\Box}$, and uniformity of 2% were measured.

• 한국전기전자재료학회논문지
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• 제12권1호
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• pp.18-26
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• 1999

In this study, the undoped amorphous layers and phosphorus doped amorphous layers are fabricated using LPCVD at 531$^{\circ}C$ with SiH$_4$ gas or at same temperature with PH$_3$ gas during deposition, respectively. The thickness of deposited amorphous layer from this experiments was 5000 ${\AA}$. In this experiments, undoped amorphous layers are deposited with SiH$_4$and Si$_2$H$\_$6/ gas in a low pressure reactor using LPCVD. These amorphous layers can be doped for poly-silicon by phosphorus ion implantation. The experiments of this study are carried out by phosphorus ion implantation with energy 40 keV into P doped and undoped amorphous silicon layers. The distribution of phosphorus profiles are measured by SIMS(Cameca 6f). Recoiling effects and two dimensional profiles are also explained by comparisions of experimental and simulated data. Finally range moments of SIMS profiles are calculated and compared with simulation results.

• 한국전기전자재료학회논문지
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• 제11권9호
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• pp.705-710
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• 1998

Intrinsic gettering is usually to improve wafer quality, which is an important factor for reliable ULSI devices. In order to generate oxygen precipitation in lightly and heavily boron doped silicon wafers with or without high $^75 As^+$ ion implantation, the 2-step annealing method was adopted. After annealing, the were cleaved and etched with th Wright etchant. The morphology of cross section on samples was inspected by FESEM(field emission scanning electron microscopy). The morphology of unimplanted samples was rater rough than that of the implanted. Oxygen precipitation density observed by an optical microscope in lightly boron doped samples was about 3$\times10^6/cm^3$. However, in heavily boron doped samples, the density of oxygen precipitation was largest at $600^{\circ}C$ in 1st annealing, and decreased abruptly until $800^{\circ}C$, But it increased slightly at $1000^{\circ}C$ and was independent with the implantation.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 춘계학술발표강연 및 눈문개요집
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• pp.31-31
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• 1999

• 대한전자공학회논문지
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• 제27권4호
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• pp.541-546
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• 1990

The current conduction and dielectric breakdown properties of oxide grown on phosphorous-doped polysilicon have been investigated by means of the ramped I-V measurements. The effective barrier heights of polyoxide grown by different silicon deposition and oxidation conditions were calculated from the Fowler-Nordheim tunneling characteristic. The average critical fields were also obtained for each film. From the results, the high temperature oxided polyoxide grown on amorphous silicon film shows superior electrical characteristics comparing to the other films.

• 비파괴검사학회지
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• 제37권1호
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• pp.1-6
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• 2017

본 논문에서는 테라헤르츠파 시간분광영상시스템을 이용하여 도핑된 실리콘 웨이퍼의 물리적 특성을 측정하는 것에 관한 연구를 진행하였다. 투과모드와 $30^{\circ}$의 입사각을 가진 반사모드를 이용하여 측정하였으며 실리콘 웨이퍼의 도핑 정도는 N-type과 P-type 모두에서 $10^{14}$에서 $10^{18}$까지 다양하게 준비하였다. 그 결과, 도핑 정도와 테라헤르츠파와의 상관관계를 찾았으며 이를 이용하면 모든 경우에 대한 도핑된 실리콘 웨이퍼의 도핑 정도를 확인할 수 있다. 또한, 각 도핑된 실리콘 웨이퍼의 도핑된 두께, 굴절률, 유전율을 테라헤르츠 시간영역 파형분석을 통하여 계산할 수 있었다. 따라서, 테라헤르츠 시간분광영상화 기술은 도핑된 실리콘 웨이퍼의 굴절률과 유전율과 같은 물리적 특성뿐만 아니라 도핑 정도를 측정할 수 있는 유용한 기술이 될 것으로 기대된다.

• 통합자연과학논문집
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• 제2권3호
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• pp.202-206
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• 2009

Optical images based on the porous silicon exhibiting photoluminescence have been prepared from an electrochemical etching of n-type silicon wafer (boron-doped,<100> orientation, resistivity $1{\sim}10{\Omega}-cm$) by using a beam projector. The images remained in the substrate displayed an optical images correlating to the optical pattern and could be useful for optical data storage. This provides the ability to fabricate complex optical encoding in the surface of silicon.

• 전자공학회논문지A
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• 제33A권2호
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• pp.96-113
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• 1996

고농도로 붕소가 도핑된 실리콘층 내에 존재하는 부정합 전위는 웨이퍼 가장자리에서 발생됨을 알았으며, 이 층을 도핑되지 않은 영역으로 둘러쌓음으로써 부정합 전위가 억제된 고농도로 붕소가 도핑된 실리콘층을 형성할 수 있었다. 이를 이용하여 부정합 전위가 없는 고농도로 붕소가 도핑된 실리콘 멤브레인을 제작하였으며, 이 멤브레인의 표면 거칠기 및 파괴 강도 그리고 잔류 인장 응력을 각각 20$\AA$ 1.39${\times}10^{10}dyn/cm^{2}$ 그리고 2.7${\times}10^{9}dyn/cm^{2}$로 측정되었다. 반면에 부정합 전위를 포함하는 기존 멤브레인은 각각 500$\AA$ 8.27${\times}10^{9}dyn/cm^{2}$ 그리고 9.3${\times}10^{8}dyn/cm^{2}$로 측정되었으며, 두 멤브레인의 이러한 차이는 부정합 전위에서 기인함을 알았다. 측정된 두 멤브레인의 Young's 모듈러스는 1.45${\times}10^{12}dyn/cm^{2}$로 동일하게 나타났다. 또, 도핑 농도 1.3${\times}10^{12}dyn/cm^{3}$에 대한 고농도로 붕소가 도핑된 실리콘의 유효 격자 상수 및 기존 멤브레인의 평면적 격자 상수 그리고 기존 멤브레인 내의 부정합 전위의 밀도는 각각 5.424$\AA$ 5.426$\AA$ 그리고 2.3${\times}10^{4}$/cm 로 추출되었으며, 붕소가 도핑된 실리콘의 부정합 계수는 1.04${\times}10^{23}$/atom으로 추출되었다. 한편 별도의 추가적인 공정없이 일반적인 에피 성장법을 사용하여 고농도로 붕소가 도핑된 실리콘층 위에 부정합 전위가 없는 에피 실리콘을 성장시켰으며, 이 에피 실리콘의 결정성은 매우 양호한 것으로 밝혀졌다. 또 부정합 전위가 없는 에피 실리콘에 n+/p 게이트 다이오드를 제작하고 그 전압-전류 특성을 측정한 결과 5V의 역 바이어스에서 0.6nA/$cm^{2}$의 작은 누설 전류값을 나타내었다.

• 한국재료학회지
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• 제21권9호
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• pp.491-496
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• 2011

Transparent conducting oxides (TCOs) used in the antireflection layer and current spreading layer of heterojunction solar cells should have excellent optical and electrical properties. Furthermore, TCOs need a high work function over 5.2 eV to prevent the effect of emitter band-bending caused by the difference in work function between emitter and TCOs. Sn-doped $In_2O_3$ (ITO) film is a highly promising material as a TCO due to its excellent optical and electrical properties. However, ITO films have a low work function of about 4.8 eV. This low work function of ITO films leads to deterioration of the conversion efficiency of solar cells. In this work, ITO films with various Zn contents of 0, 6.9, 12.7, 28.8, and 36.6 at.% were fabricated by a co-sputtering method using ITO and AZO targets at room temperature. The optical and electrical properties of Zn-doped ITO thin films were analyzed. Then, silicon heterojunction solar cells with these films were fabricated. The 12.7 at% Zn-doped ITO films show the highest hall mobility of 35.71 $cm^2$/Vsec. With increasing Zn content over 12.7, the hall mobility decreases. Although a small addition of Zn content increased the work function, further addition of Zn content over 12.7 at.% led to decreasing electrical properties because of the decrease in the carrier concentration and hall mobility. Silicon heterojunction solar cells with 12.7 at% Zn-doped ITO thin films showed the highest conversion efficiency of 15.8%.

• 한국결정성장학회지
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• 제15권6호
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• pp.260-262
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• 2005

Thickness optimization of heavily doped p-type seeding layer was studied to improve performance of thin film silicon solar cell. We used liquid phase epitaxy (LPE) to grow active layer of $25{\mu}m$ thickness on $p^+$ seeding layer. The cells with $p^+$ seeding layer of $10{\mu}m\;to\;50{\mu}m$ thickness were fabricated. The highest efficiency of a cell is 12.95%, with $V_{oc}=633mV,\;J_{sc}=26.5mA/cm^2$, FF = 77.15%. The $p^+$ seeding layer of the cell is $20{\mu}m$ thick. As thicker seeding layer than $20{\mu}m$, the performance of the cell was degraded. The results demonstrate that the part of the recombination current is due to the heavily doped seeding layer. Thickness of heavily doped p-type seeding layer was optimized to $20{\mu}m$. The performance of solar cell is expected to improve with the incorporation of light trapping as texturing and AR coating.