Blue emission in porous silicon: Oxygen-related photoluminescence

1994 ◽  
Vol 49 (11) ◽  
pp. 7821-7824 ◽  
Author(s):  
L. Tsybeskov ◽  
Ju. V. Vandyshev ◽  
P. M. Fauchet
1996 ◽  
Vol 452 ◽  
Author(s):  
Gildardo R. Delgado ◽  
Howard W.H. Lee ◽  
Susan M. Kauzlarich ◽  
Richard A. Bley

AbstractWe studied the optical and electronic properties of silicon nanocrystals derived from two distinct fabrication procedures. One technique uses a controlled chemical reaction. In the other case, silicon nanocrystals are produced by ultrasonic fracturing of porous silicon layers. We report on the photoluminescence, photoluminescence excitation, and absorption spectroscopy of various size distributions derived from these techniques. We compare the different optical properties of silicon nanocrystals made this way and contrast them with that observed in porous silicon. Our results emphasize the dominant role of surface states in these systems as manifested by the different surface passivation layers present in these different fabrication techniques. Experimental absorption measurements are compared to theoretical calculations with good agreement. Our results provide compelling evidence for quantum confinement in both types of Si nanocrystals. Our results also indicate that the blue emission from very small Si nanocrystals corresponds to the bandedge emission, while the red emission arises from traps.


2014 ◽  
Vol 1052 ◽  
pp. 181-187
Author(s):  
Yan Li Ding ◽  
Yue Zhao ◽  
Yue Feng ◽  
Xiao Yan Liang ◽  
Lin Jun Wang ◽  
...  

Photoluminescence of porous silicon (PS) prepared by different etched time was studied. The photoluminescence might originate from the recombination of carriers and surface states, which was proved by FTIR, Raman spectroscopy and SEM. Furthermore, the hydrogen-related groups on the PS surface could eliminate the surface states for the blue emission, but the quantities of surface states for the green emission were depended on the uncovered area on the PS surface. Moreover, the shape of photoconductivity curve was depended on the quantities of the surface states, which also was related to the uncovered area on the PS surface. In addition, the results of the microwave-detected photoconductivity decay measurement indicated thatthe defects on the PS surface increased with the increase of the etched time, which would be related to the increase of the depth of pores.


2005 ◽  
Vol 40 (18) ◽  
pp. 5071-5073 ◽  
Author(s):  
Yue Zhao ◽  
Dongsheng Li ◽  
Deren Yang ◽  
Minghua Jiang
Keyword(s):  

1993 ◽  
Vol 298 ◽  
Author(s):  
Y. Kanemitsu ◽  
T. Matsumoto ◽  
T. Futagi ◽  
H. Mimura

AbstractWe have studied the origin of the visible photoluminescence (PL) from oxidized porous Si. The hydrogen–passivated surface of porous Si prepared by electrochemical etching is converted to stable silicon oxides by rapid–thermal–oxidization processes. At low oxidation temperature (Tox), the PL spectrum with a peak near 700 nm is observed. At high Tox above 800 °C, a strong blue PL is observed near 400 nm. We discuss the origin of blue and red PL by employing the results of ab initio electronic structure calculations of silicon–oxygen compounds.


2017 ◽  
Vol 24 (Supp02) ◽  
pp. 1850017
Author(s):  
MAHMOOD BAHAR ◽  
ENSIEH KHALILI DERMANI

The porous silicon (PSi), which is produced by the electrochemical etching, has been used as a substrate for the growth of the titanium oxide (TiO2) thin films. By using the EBPVD method, TiO2thin films have been deposited on the surface of the PSi substrate. TiO2/PSi layers were annealed at the temperature of 400[Formula: see text]C, 500[Formula: see text]C and 600[Formula: see text]C for different tests. The morphology and structures of layers were investigated by the scanning electron microscopy (SEM) and X-ray diffraction (XRD). The current–voltage characteristic curves of samples and the ideality factor of heterojunction were studied. The results showed that the electrical properties of the samples change with increase in the annealing temperature. The optical properties of the prepared samples were investigated by using UV–Vis and photoluminescence (PL) spectroscopy. Green light emission of the PSi combined with the blue light and violet–blue emission obtained from the TiO2/PSi PL spectra. The results showed that the optical band gap energy of the PSi has increased from 1.86[Formula: see text]eV to 2.93[Formula: see text]eV due to the deposition of TiO2thin film.


1998 ◽  
Vol 47 (1) ◽  
pp. 124
Author(s):  
LI PENG ◽  
MA YU-RONG ◽  
FANG RONG-CHUAN ◽  
HU KE-LIANG

2005 ◽  
Vol 486-487 ◽  
pp. 21-24
Author(s):  
Hyun Ah Park ◽  
K. Prabakar ◽  
Yeon Chul Yoo ◽  
Sun Keun Hwang ◽  
Chong Mu Lee

Al doped ZnO (AZO) films were deposited on porous silicon (PS) substrates by a reactive rf-cosputtering process from two targets of ZnO and Al. The effect of ZnO target rf-sputtering power on the structural and photoluminescence (PL) properties of AZO/PS heterojunctions were studied. Strong monochromatic blue emission located at 2.78 eV was observed for the AZO films deposited at 150 W. Freshly prepared PS showed an emission band in the green spectral region. We show that deposition of AZO on PS does not degrade the skeleton of the PS and enhance the PL intensity. The PL band shifted to the high energy for AZO films deposited on PS and the intensity became stable.


2007 ◽  
Vol 4 (2) ◽  
pp. 501-504
Author(s):  
R. K. Tyagi ◽  
Pankaj Pathak
Keyword(s):  

1998 ◽  
Vol 83 (3) ◽  
pp. 1776-1778 ◽  
Author(s):  
Hideki Koyama ◽  
Yuka Matsushita ◽  
Nobuyoshi Koshida

1994 ◽  
Vol 65 (19) ◽  
pp. 2451-2453 ◽  
Author(s):  
C. I. Harris ◽  
M. Syväjärvi ◽  
J. P. Bergman ◽  
O. Kordina ◽  
A. Henry ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document