scholarly journals Laser recrystallization and inscription of compositional microstructures in crystalline SiGe-core fibres

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
David A. Coucheron ◽  
Michael Fokine ◽  
Nilesh Patil ◽  
Dag Werner Breiby ◽  
Ole Tore Buset ◽  
...  
1984 ◽  
Vol 35 ◽  
Author(s):  
A.J. Auberton-Herve ◽  
J.P. Joly ◽  
J.M. Hode ◽  
J.C. Castagna

ABSTRACTSeeding from bulk silicon (lateral epitaxy) has been used in Ar+ laser recrystallization to achieve subboundary free silicon on insulator areas. On these areas C.MOS devices have been performed using almost entirely the standard processing steps of a bulk micronic C-MOS technology. n -MOS transistors with channel length as small as 0.3 um have shown very small leakage currents. This is attributed especially to the lack of subboundaries. A 40 % increase in the dynamic performances in comparison with equivalent size C-MOS bulk devices has been obtained (93 ps of delay time per stage for a 101 stages ring oscillator with 0.8 μm of channel length). This is the best result presented so far on recrystallized SOI. No special requirements are needed in the lay out of the circuit with the chosen seed structure. Furthermore an industrial processing rate for the laser recrystallization processing has been achieved using an elliptical laser beam, a high scan velocity (30 cm/s) and a 100 μm line to line scan step (a 4' wafer in 4 minutes).


2001 ◽  
Vol 685 ◽  
Author(s):  
Minghong Lee ◽  
Seungjae Moon ◽  
Mutsuko Hatano ◽  
Costas P. Grigoropoulos

AbstractA new double laser recrystallization technique that can produce lateral grains of tens of micrometers is presented. A nanosecond laser (excimer or Nd:YLF laser) and a pulse modulated Ar+ laser are used in the experiment. The effect of different parameters on lateral grain growth is investigated. These parameters include the time delay between the two lasers, the excimer laser fluence, the Ar+ laser power and the pulse duration. This process has wide process window and is insensitive to both the excimer laser fluence and the Ar+ laser power fluctuations. Preheating and melting of the a-Si film with the Ar+ laser before firing the excimer laser is found to be necessary for inducting lateral grain growth. The transient excimer laser irradiation is believed to generate nucleation sites for initiating the subsequent lateral grain growth. The solidification dynamics of the process is probed by high spatial and temporal resolution laser flash photography. A lateral solidification velocity of about 10 m/s is observed.


2000 ◽  
Vol 266-269 ◽  
pp. 645-649 ◽  
Author(s):  
Jae-Hong Jeon ◽  
Kee-Chan Park ◽  
Min-Cheol Lee ◽  
Min-Koo Han

Author(s):  
Martin Y. Zhang ◽  
Qiong Nian ◽  
Gary J. Cheng

In this study, a method combining room temperature pulsed laser deposition (PLD) and direct pulsed laser recrystallization (DPLR) are introduced to deposit superior transparent conductive oxide (TCO) layer on low melting point flexible substrates. As an indispensable component of thin film solar cell, TCO layer with a higher quality will improve the overall performance of solar cells. Alumina-doped zinc oxide (AZO), as one of the most promising TCO candidates, has now been widely used in solar cells. However, to achieve optimal electrical and optical properties of AZO on low melting point flexible substrate is challenging. Recently developed direct pulsed laser recrystallization (DPLR) technique is a scalable, economic and fast process for point defects elimination and recrystallization at room temperature. It features selective processing by only heating up the TCO thin film and preserve the underlying substrate at low temperature. In this study, 250 nm AZO thin film is pre-deposited by pulsed laser deposition (PLD) on flexible and rigid substrates. Then DPLR is introduced to achieve a uniform TCO layer on low melting point flexible substrates, i.e. commercialized Kapton polyimide film and micron-thick Al-foil. Both finite element analysis (FEA) simulation and designed experiments are carried out to demonstrate that DPLR is promising in manufacturing high quality AZO layers without any damage to the underlying flexible substrates. Under appropriate experiment conditions, such as 248 nm in laser wavelength, 25 ns in laser pulse duration, 15 laser pulses at laser fluence of 25 mJ/cm2, desired temperature would result in the AZO thin film and activate the grain growth and recrystallization. Besides laser conditions, the thermal conductivity and crystallinity of the substrate serve as additional factors in the DPLR process. It is found that the substrate’s thermal conductivity correlates positively with the AZO crystal size; the substrate’s crystallinity correlates positively with the AZO film’s crystallinity. The thermal expansion of substrate would also contribute to the film tensile stress after processed by DPLR technique. The overall results indicate that DPLR technique is useful and scalable for flexible solar cell manufacturing.


2003 ◽  
Vol 769 ◽  
Author(s):  
Sang-Myeon Han ◽  
Min-Cheol Lee ◽  
Su-Hyuk Kang ◽  
Moon-Young Shin ◽  
Min-Koo Han

AbstractAn ultra-low temperature (< 200°C) polycrystalline silicon (poly-Si) film is fabricated for the plastic substrate application using inductively coupled plasma chemical vapor deposition (ICP-CVD) and excimer laser annealing. The precursor active layer is deposited using the SiH4/He mixture at 150°C (substrate). The deposited silicon film consists of crystalline component as well as hydrogenated amorphous component. The hydrogen content in the precursor layer is less than 5 at%. The grain size of the precursor active silicon film is about 200nm and it is increased up to 500nm after excimer laser irradiation.


1994 ◽  
Vol 345 ◽  
Author(s):  
Yasutaka Uchida ◽  
Masakiyo Matsumura

AbstractXPS measurement showed that undesirable SiNH component was reduced drastically from the low-temperature deposited SiN surface by intense ArF excimer-laser irradiation. Although the improved layer was as thin as 15nm, it was very effective to stop diffusion of N atoms from the bottom SiN layer to the top Si layer during the excimer-laser recrystallization step. N-diffused Si layer at the Si/SiN interface was less than the XPS resolution limit for the pre-annealed SiN structure, but about 5nm thick. As a result, the field-effect mobility of the poly-Si/SiN TFT was increased drastically by laser-irradiation to SiN film. Annealing characteristics are also presented for the various SiN film thicknesses and for both the ArF and KrF excimer-laser lights.


1990 ◽  
Vol 46 (1-4) ◽  
pp. 388-391
Author(s):  
B. Hu ◽  
A. Seidl ◽  
R. Buchner ◽  
D. Bollmann ◽  
W. van der Wel ◽  
...  

1986 ◽  
Author(s):  
K. Sugahara ◽  
S. Kusunoki ◽  
Y. Inoue ◽  
T. Nishimura ◽  
Y. Akasaka

Sign in / Sign up

Export Citation Format

Share Document