TY - JOUR
T1 - Strong ultraviolet electroluminescence from porous silicon light-emitting diodes
AU - TAM, Hoi Lam
AU - Yuan, J.
AU - Li, K. F.
AU - WONG, Rick W K
AU - CHEAH, Kok Wai
N1 - Funding Information:
We thank S. C. Chen and P. N. Wang for many useful discussions. This project is supported by Research Grant Council of Hong Kong and FRG Grant of Hong Kong Baptist University. * to whom all correspondence should be addressed to.
PY - 2001
Y1 - 2001
N2 - Porous silicon light-emitting diodes were found to emit strong line-shaped ultraviolet under a forward bias driving voltage of about 20 volts. The intensity was sufficiently strong to pump an organic crystal, Tb-dipicolinic acid, producing clear Tb 4f intra-shell transition photoluminescence spectrum. The current-voltage characteristics of the devices also showed negative differential resistance, which was frequency dependent. In addition, purging of the device with various gases could quench the electroluminescence but the intensity recovered partially after each purging, but with no change in emission spectrum. Both results indicate the transport was influenced strongly by local space charge. From the results, the electroluminescence mechanism is tentatively attributed to core recombination in the porous layer, and the spectral characteristics is due to the microcavity effect between the top Au contact and silicon substrate. The present study shows that porous silicon has the potential as UV source in optoelectronics applications.
AB - Porous silicon light-emitting diodes were found to emit strong line-shaped ultraviolet under a forward bias driving voltage of about 20 volts. The intensity was sufficiently strong to pump an organic crystal, Tb-dipicolinic acid, producing clear Tb 4f intra-shell transition photoluminescence spectrum. The current-voltage characteristics of the devices also showed negative differential resistance, which was frequency dependent. In addition, purging of the device with various gases could quench the electroluminescence but the intensity recovered partially after each purging, but with no change in emission spectrum. Both results indicate the transport was influenced strongly by local space charge. From the results, the electroluminescence mechanism is tentatively attributed to core recombination in the porous layer, and the spectral characteristics is due to the microcavity effect between the top Au contact and silicon substrate. The present study shows that porous silicon has the potential as UV source in optoelectronics applications.
UR - http://www.scopus.com/inward/record.url?scp=0035744707&partnerID=8YFLogxK
U2 - 10.1557/proc-667-g7.10
DO - 10.1557/proc-667-g7.10
M3 - Conference article
AN - SCOPUS:0035744707
SN - 0272-9172
VL - 667
SP - G7101-G7106
JO - Materials Research Society Symposium Proceedings
JF - Materials Research Society Symposium Proceedings
T2 - Luminescent and Lumiescent Materials
Y2 - 17 April 2001 through 19 April 2001
ER -