• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.75-87
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• 1996

This review is presented under the following headings: 1.Introduction 1.1 Brief review of the properties of AlN 1.2 Historical survey of work on ceramic and single crystal AlN 2.Thermochemical background 3.Crystal growth 4.Doping 5.Potential applications and future work The known properties of AlN which make it of interest for various are discussed briefly. The properties include chemical stability, crystal structure and lattice constants, refractive indices and other optical properties, dielectric constant, surface acoustic wave velocity and thermal conductivity. The history of work in single crystals, thin films and ceramics are outlined and the thermochemistry of AlN reviewed together with some of the relevant properties of aluminium and nitrogen; the problems encountered in growing crystals of AlN are shown to arise directly from these thermochemical relationships. Methods have been reported in the literature for growing AlN crystals from melts, solution and vapour and these methods are compared critically. It is proposed that the only practicable approach to the growth of AlN is by vapour phase methods. All vapour based procedures share the share the same problems: $.$the difficulty of preventing contamination by oxygen & carbon $.$the high bond energy of molecular nitrogen $.$the refractory nature of AlN (melting point~3073K at 100ats.) $.$the high reactivity of Al at high temperatures It is shown that the growth of epitactic layers and polycrystalline layers present additional problems: $.$chemical incompatibility of substrates $.$crystallographic mismatch of substrates $.$thermal mismatch of substrates The result of all these problems is that there is no good substrate material for the growth of AlN layers. Organometallic precursors which contain an Al-N bond have been used recently to deposit AlN layers but organometallic precursors gave the disadvantage of giving significant carbon contamination. Organometallic precursors which contain an Al-N bound have been used recently to deposit AlN layers but organometallic precursors have the disadvantage of giving significant carbon contamination. It is conclude that progress in the application of AlN to optical and electronic devices will be made only if considerable effort is devoted to the growth of larges, pure (and particularly, oxygen-free) crystals. Progress in applications of epi-layers and ceramic AlN would almost certainly be assisted also by the availability of more reliable data on the pure material. The essential features of any stategy for the growth of AlN from the vapour are outlined and discussed.

• 열처리공학회지
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• 제18권5호
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• pp.281-287
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• 2005

Titanium aluminium nitride((TiAl)N) film is anticipated as an advanced coating film with wear resistance used for drills, bites etc. and with corrosion resistance at a high temperature. In this study, (TiAl)N thin films were deposited both at room temperature and at elevated substrate temperatures of 573 to 773 K by using a two-facing-targets type DC sputtering system in a mixture Ar and $N_2$ gases. Atomic compositions of the binary Ti-Al alloy target is Al-rich (25Ti-75Al (atm%)). Process parameters such as precursor volume %, substrate temperature and Ar/$N_2$ gas ratio were optimized. The crystallization processes and phase transformations of (TiAl)N thin films were investigated by X-ray diffraction, field-emission scanning electron microscopy. The microhardness of (TiAl)N thin films were measured by a dynamic hardness tester. The films obtained with Ar/$N_2$ gas ratio of 1:3 and at 673 K substrate temperature showed the highest microhardness of $H_v$ 810. The crystallized and phase transformations of (TiAl)N thin films were $Ti_2AlN+AlN{\rightarrow}TiN+AlN$ for Ar/$N_2$ gas ratio of 1:3, $Ti_2AlN+AlN{\rightarrow}TiN+AlN{\rightarrow}Ti_2AlN+TiN+AlN$ for Ar/$N_2$ gas ratio of 1:1 and $TiN+AlN{\rightarrow}Ti_2AlN+TiN+AlN{\rightarrow}Ti_2AlN+AlN{\rightarrow}Ti_2AlN+TiN+AlN$ for Ar/$N_2$ gas ratio of 3:1. The above results are discussed in terms of crystallized phases and microhardness.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.51-55
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• 2011

In this paper, the optimized doping condition of crystalline silicon solar cells with 156 ${\times}$ 156 mm2 area was studied. To optimize the drive-in condition in the doping process, the other conditions except drive-in temperature and time were fixed. After etching 7 ${\mu}m$ of the surface to form the pyramidal structure, the silicon nitride deposited by the PECVD had 75~80 nm thickness and 2 to 2.1 for a refractive index. The silver and aluminium electrodes for front and back sheet, respectively, were formed by screen-printing method, followed by firing in $400-425-450-550-850^{\circ}C$ five-zone temperature conditions to make the ohmic contact. Drive-in temperature was changed in range of $828^{\circ}C$ to $860^{\circ}C$ and time was from 3 min to 40 min. The sheet resistance of wafer was fixed to avoid its effect on solar cell. The solar cell fabricated with various conditions showed the similar conversion efficiency of 17.4%. This experimental result showed the drive-in temperatures and times little influence on solar cell characteristics.

• 한국태양에너지학회 논문집
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• 제31권1호
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• pp.37-43
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• 2011

In this paper, the optimized doping condition of crystalline silicon solar cells with $156{\times}156\;mm^2$ area was studied. To optimize the drive-in temperature in the doping process, the other conditions except variable drive-in temperature were fixed. These conditions were obtained in previous studies. After etching$7\;{\mu}m$ of the surface to form the pyramidal structure, the silicon nitride deposited by the PECVD had 75~80nm thickness and 2 to 2.1 for a refractive index. The silver and aluminium electrodes for front and back sheet, respectively, were formed by screen-printing method, followed by firing in 400-425-450-550-$850^{\circ}C$ five-zone temperature conditions to make the ohmic contact. Drive-in temperature was changed in range of $830^{\circ}C$ to $890^{\circ}C$to obtain the sheet resistance $30{\sim}70\;{\Omega}/{\box}$ with $10\;\Omega}/{\box}$ intervals. Solar cell made in $890^{\circ}C$ as the drive-in temperature revealed 17.1% conversion efficiency which is best in this study. This solar cells showed $34.4\;mA/cm^2$ of the current density, 627 mV of the open circuit voltage and 79.3% of the fill factor.

• 한국ITS학회 논문지
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• 제7권5호
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• pp.97-105
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• 2008

반도체 공정의 미세화 및 마이크로 시스템 기술의 발전 그리고 소형 무선PAN 및 이동통신 장치들의 급증으로 인하여 전자부품들의 소형화와 직접화에 대한 요구가 지속적으로 증가되고 있다. 본 연구에서는 휴대형 무선PAN 및 이동통신용 전자회로 설계에 다양한 목적으로 널리 사용되고 있는 기저대역의 수동소자들 중 미세 커패시터의 안정성과 전기적 특성을 확보하기 위하여, 유전체인 AIN을 사용하여 MIM구조로 제작된 미세 박막 커패시터 소자의 전기적인 특성을 분석하고 기저대역에서의 성능을 평가한다. 또한 제작된 미세 박막형 커패시터의 용량제어 방법을 제시함으로서 기저대역에서 범용으로 사용할 수 있는 미세 박막 커패시터의 모델을 제시하고자 한다. 또한, 주파수 대역에 따른 MIM구조의 AIN 커패시터 특성을 분석함으로서 향후 임베디드 소자와 집적화를 위한 고정밀의 미세수동 소자로서의 활용방안을 제시하고자한다.

• 대한치과보철학회지
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• 제54권4호
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• pp.354-363
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• 2016

목적: 본 연구는 지르코니아 도재 표면의 나노구조 알루미나 코팅이 지르코니아와 레진 시멘트와의 전단결합강도에 미치는 영향을 알아보고자 하였다. 재료 및 방법: 지르코니아 원판 80개를 표면처리방법(산화알루미늄 분사처리(A), 산화알루미늄 분사 후 Rocatec 처리(R), 연마 후 나노구조 알루미나 코팅(PC), 산화알루미늄 분사 후 나노구조 알루미나 코팅(AC))에 따라 4개의 군으로 나누었다. 알루미나 코팅은 질산 알루미늄을 가수분해시킨 용액에 침적 후 $900^{\circ}C$에서 열처리 하여 시행하였다. 지르코니아 표면 코팅은 주사전자 현미경을 이용하여 관찰하였다. 레진 블럭을 레진 시멘트를 이용하여 각 실험군의 지르코니아 표면에 합착하고 열순환처리 전, 후의 전단결합강도를 측정하였다. 결과: 알루미나 코팅을 한 지르코니아 표면은 균일하고 치밀한 나노구조 알루미나가 관찰되었다. PC, AC 군은 열순환처리 전과 후 모두 A와 R 군에 비해 현저하게 높은 전단결합 강도를 보였다. A, R 군은 열순환처리 후에 급격한 결합강도의 감소를 보였으나, PC와 AC군은 열순환처리에 의해 유의할만한 결합강도의 감소를 보이지 않았다. 결론: 지르코니아 표면에 나노구조 알루미나 코팅처리하는 것은 레진시멘트와의 결합강도를 증가시키는 방법이다.