• E2M - 전기 전자와 첨단 소재
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• 제11권11호
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• pp.22-27
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• 1998

We have investigated the effect of an ion shower doping of the laser annealed poly-Si films at an elevated substrate temperatures. The substrate temperature was varied from room temperature to 300$^{\circ}C$ when the poly-Si film was doped with phosphorus by a non-mass-separated ion shower. Optical, structural, and electrical characterizations have been performed in order to study the effect of the ion showering doping. The sheet resistance of the doped poly-Si films was decreased from7${\times}$106 $\Omega$/$\square$ to 700 $\Omega$/$\square$ when the substrate temperature was increased from room temperature to 300$^{\circ}C$. This low sheet resistance is due to the fact that the doped film doesn't become amorphous but remains in the polycrystalline phase. The mildly elevated substrate temperature appears to reduce ion damages incurred in poly-Si films during ion-shower doping. Using the ion-shower doping at 250$^{\circ}C$, the field effect mobility of 120 $\textrm{cm}^2$/(v$.$s) has been obtained for the n-channel poly-Si TFTs.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.95-97
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• 2004

We studied a low temperature ion doping process for poly-Si Thin Film Transistor (TFT) on plastic substrates. The ion doping process was performed using an ion shower system, and subsequently, excimer laser annealing (ELA) was done for the activation. We have studied the crystallinity of Si surface at each step using UV-reflectance spectroscopy and the sheet resistance using 4-point probe. We found that the temperature has increased during ion shower doping for a-Si film and the activation has not been fulfilled stably because of the thermal damage against the plastic substrate. By trying newly a pulsed ion shower doping, the ion was efficiently incorporated into the a-Si film on plastic substrate. The sheet resistance decreased with the increase of the pulsed doping time, which was corresponded to the incorporated dose. Also we confirmed a relationship between the crystallinity and the sheet resistance. A sheet resistance of 300 ${\Omega}$/sq for the Si film of 50nm thickness was obtained with a good reproducibility. The ion shower technique is a promising doping technique for ultra low temperature poly-Si TFTs on plastic substrates as well as those on glass substrates.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
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• pp.178-178
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• 1999

• Journal of Information Display
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• 제5권1호
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• pp.1-6
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• 2004

Ion shower doping with a main ion source of $P_2H_x$ using a source gas mixture of $PH_3/H_2$ was conducted on excimer-laser- annealed (ELA) poly-Si. The crystallinity of the as-implanted samples was measured using a UV-transmittance. The measured value of as-implanted damage was found to correlate well with the one calculated through/obtained from TRIM-code simulation. The sheet resistance was found to decrease as the acceleration voltage increased from 1 kV to 15 kV at a doping time of 1 min. However, it increases as the acceleration voltage increases under severe doping conditions. Uncured damage after furnace annealing is responsible for the rise in sheet resistance.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.752-755
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• 2006

Reverse annealing was observed in $P^+/B^+$ ion shower doped poly-Si upon activation annealing. Phosphorous or boron was implanted by ion shower doping using a source gas mixture of $PH_3/H_2$ or $B_2H_6/H_2$. Activation annealing was conducted using a tube furnace in the temperature ranges from $350^{\circ}C$ to $650^{\circ}C$. Hall measurement revealed that reverse annealing begins at different annealing temperatures for poly-Si implanted with P and B, respectively. It was observed that reverse annealing starts at $550^{\circ}C$$ in $P^+$ ion shower doped poly-Si, while at $350^{\circ}C$ in the case of B-doping.

• 전자공학회논문지A
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• 제31A권5호
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• pp.106-112
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• 1994

We have developed a large area ion shower doping system with an RF plasma ion source. The ion current density (i.e., doping concentration) increases with RF power and acceleration voltage. Using this technique, we investigated the optimum condition for ion doping of phosphorus in a-Si:H and poly-Si films. The optimum acceleration voltage and doping time are 6KV and 90sec, respectively, in a-Si:H films. Under this condition the electrical conductivity of ion-doped a-Si:H film is obtained ~10$^{-3}$/cm at room temperature. The sheet resistance decreases witnh acceleration voltage in ion-doped poly-Si, and a heavily-doped layer with a sheet resistance of 920$\Omega$/ㅁ is obtained by using ion doping and subsequent activation.

• 전기화학회지
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• 제8권1호
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• pp.24-31
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• 2005

Ion-Shower-Doping장비 및 $PH_/3M_2$혼합 가스를 사용하여 Phosphorous를 ELA방법으로 제조된 Poly-Si에 가속 전압 및 조사량을 변수로 이온 주입하였다. As-implanted된 시편의 결정도는 UV-transmittance spectroscopy를 사용하여 측정하였다. 이 때 UV-transmittance를 이용하여 측정한 값은 Raman spectroscopy를 이용해서 측정한 값과 서로 관련되어 있음을 알았다. 면 저항은 가속전압이 1kV에서 15kV까지 증가함에 따라 감소한다 그러나 가혹한 도핑조건하에서는 가속전압의 증가 시 면 저항이 증가한다. 이는 활성화 열처리 후 치유되지 않은 결함에 의해 전자가 포획되며 이에 따라 전하 운반자의 농도가 감소하는 때문이다. 활성화 열처리는 로열처리, RTA 열처리, ELA 열처리 등의 방법으로 수행하였고 열처리 방법에 따르는 도펀트의 활성화 및 결함의 회복의 거동을 연구하였다

• 전자공학회논문지A
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• 제32A권1호
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• pp.146-151
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• 1995

We have studied the fabrication self aligned atmospheric pressure(AP) CVD a-Si thin film transistor with source-drain ohmic contact by using ion shower doping method. The conductivity is 6*10$^{-2}$S/cm when the acceleration voltage, doping time and doping temperature are 6kV, 90s and 350.deg. C, respectively. We obtained the field effect mobility of 1.3cm$^{2}$/Vs and the threshold voltage of 7V.

• 한국진공학회지
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• 제4권S2호
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• pp.34-39
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• 1995

we have studied the possibility of n-type doping in diamond and DLC films. After ion doping of either p-type or n-type, the electrical conductivities were remarkably increased and conductivity activation energies were decreased. The Raman intensity at 1330 cm-1 decreases slightly by ion doping of $7.2\times 10^{16}\; \textrm{cm}^{-2}$. The increase in conductivity by ion doping appears to be arised from the combined effects by substitutional doping and graphitization by ion damage.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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• pp.117-117
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• 2003