• Journal of Information Display
• /
• v.11 no.1
• /
• pp.12-16
• /
• 2010

The effect of the crystallization and activated annealing of Si films using an excimer laser and the new CW blue laser are described and compared with furnace annealing for application in advanced TFTs and for future applications. Pulsed excimer laser annealing (ELA) is currently being used extensively as a low-temperature poly-silicon (LTPS) process on glass substrates as its efficiency is high in the ultra-violet (UV) region for thin Si films with thickness of 40-60 nm. ELA enables extremely low resistivity relating to high crystallinity for both the n- and p-type Si films. On the other hand, CW blue laser diode annealing (BLDA) enables the smooth Si surface to have arbitral crystal grains from micro-grains to an anisotropic huge grain structure only by controlling its power density. Both annealing techniques are expected to be applied in the future advanced TFT systems.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.1162-1165
• /
• 2006

In this paper, the characteristics of polycrystalline silicon thin-film transistors (poly- Si TFTs) fabricated on polymer substrates are investigated. The a-Si films was laser annealed by using a XeCl excimer laser and a four-mask-processed poly-Si TFT was fabricated with fully self-aligned top gate structure. The fabricated nMOS TFT showed field-effect mobility of ${\sim}30\;cm^2/Vs$, on/off ratio of $10^5$ and threshold voltage of 5 V.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.413-418
• /
• 2006

Highly stable thin-film transistor (TFT) pixel employing both low temperature polycrystalline silicon (LTPS) and amorphous silicon (a-Si) for active matrix organic light emitting diode (AMOLED) is discussed. ELA (excimer laser annealing) LTPS-TFT pixel should compensate $I_{OLED}$ variation caused by the non-uniformity of LTPS-TFT due to the fluctuation of excimer laser energy and amorphous silicon TFT pixel is desired to suppress the decrease of $I_{OLED}$ induced by the degradation of a-Si TFT. We discuss various compensation schemes of both LTPS and a-Si TFT employing the voltage and the current programming.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07b
• /
• pp.1123-1126
• /
• 2005

For creation of low temperature polycrystallinesilicon (LTPS) the line beam excimer laser annealing (ELA) is a well known and established technique in mass production. With introduction of Sequential Lateral Solidification (SLS) some aspects such as crystalline quality, throughput and flexibility regarding the substrate size could be improved, but for OLED manufacturing still further process development is necessary. This paper discusses line beam ELA and SLS techniques that might enable process engineers to make polycrystalline-silicon (poly-Si) films with a high degree of uniformity and quality as required for system on glass (SOG) and active matrix organic light emitting displays (AMOLED). Equipment requirements are discussed and compared to previous standards. SEM images of process examples are shown in order to demonstrate the viability.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.248-251
• /
• 2003

The large size grain of poly-Si film is obtained above the upper limit of excimer laser energy at which the random nucleation occurs. We simulate the time dependent temperature profile of ${\alpha}-Si/SiO_2/Si$ substrate structure according to the excimer laser energy with $ANSYS^{\circledR}$ simulator. As the thickness is increased, the laser energy for the melting of ${\alpha}-Si$ film is increased.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07b
• /
• pp.1112-1115
• /
• 2005

In this study, we performed excimer laser activation on Phosphorus or Boron doped a-Si (amorphous silicon) film. We've got a very low sheet resistance (Rs), Rs was 60 ohm/sq. with phosphorus doping and was 65 ohm/sq. with boron doping at each optimized laser irradiation condition. We've found Rs on activated thin film showed an unprecedented behavior in both cases, because Rs had a strong dependency on the crystallinity of the activated Si film.

• Proceedings of the KIEE Conference
• /
• 1989.11a
• /
• pp.79-82
• /
• 1989

We studied the epitaxial growth of GaAs/GaAs and GaAs/Si by Laser CVD with 193nm ArF pulsed excimer laser. The source gases of TMGa and AsC13 or TMGa-TMAs adducts are mixed with H2, and photolyzed above the substrate which is heated up to around 300$^{\circ}C$. Then the photolyzed atoms are deposited on the silicon or GaAs substrate. The deposited films are analyzed with ESKA depth profiling and X-ray differaction method, which shows that the films on Si and GaAs are stoichiometric and crystalized at such a low temperature. We show a clear evidence for the epitaxial growth of GaAs on Si or GaAs on GaAs at low temperature by excimer laser CVD.

• Proceedings of the KIEE Conference
• /
• 1993.11a
• /
• pp.268-271
• /
• 1993

Discharge pumped high power excimer laser is a very useful light source of ultraviolet region. In this paper. the design and operation characteristics of UV pre-ionized discharge pumped XeCl laser are discussed. Maximum output power of 890mJ at the efficiency of 1.4% was achieved with 35kV charging voltage, 3.4atm of total pressure and 10pps of pulse repetition rate. Optimum HCl pressure is considered to be between 2.5 and 3.5torr.

• ETRI Journal
• /
• v.25 no.4
• /
• pp.247-252
• /
• 2003

This paper presents results from experiments on laser-annealed SiGe-selective epitaxial growth (LA-SiGe-SEG). The SiGe-SEG technology is attractive for devices that require a low band gap and high mobility. However, it is difficult to make such devices because the SiGe and the highly doped region in the SiGe layer limit the thermal budget. This results in leakage and transient enhanced diffusion. To solve these problems, we grew in situ doped SiGe SEG film and annealed it on an XMR5121 high power XeCl excimer laser system. We successfully demonstrated this LA-SiGe-SEG technique with highly doped Ge and an ultra shallow junction on p-type Si (100). Analyzing the doping profiles of phosphorus, Ge compositions, surface morphology, and electric characteristics, we confirmed that the LA-SiGe-SEG technology is suitable for fabricating high-speed, low-power devices.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.748-751
• /
• 2000

Microlens made by laser radiation method have advantages in the easiness of their fabrication. The process is based on the projection of a chromium-on-quartz reticle on to the Polymer using a pulsed 248nm KrF excimer laser. Fabrication process is a fluence-dependent rate and density. The lens shape is defined by a rotationally symmetric sluence distribution with smooth radial variation in the image plane of the reticle. A typical lens of 50㎛ diameter was fabricated by irradiating 2000 laser pulses within 40 seconds. The experimental results show microlens fabrication by UV laser is possible and well worth studying further.