title: Enhancement in electron transport and light emission efficiency of a Si nanocrystal light-emitting diode by a SiCN/SiC superlattice structure.
abstract: We report an enhancement in light emission efficiency of Si nanocrystal (NC) light-emitting diodes (LEDs) by employing 5.5 periods of SiCN/SiC superlattices (SLs). SiCN and SiC layers in SiCN/SiC SLs were designed by considering the optical bandgap to induce the uniform electron sheet parallel to the SL planes. The electrical property of Si NC LED with SiCN/SiC SLs was improved. In addition, light output power and wall-plug efficiency of the Si NC LED with SiCN/SiC SLs were also enhanced by 50% and 40%, respectively. This was attributed to both the formation of two-dimensional electron gas, i.e., uniform electron sheet parallel to the SiCN/SiC SL planes due to the conduction band offset between the SiCN layer and SiC layer, and an enhanced electron transport into the Si NCs due to a lower tunneling barrier height. We show here that the use of the SiCN/SiC SL structure can be very useful in realizing a highly efficient Si NC LED.
authors.affiliation: IT Convergence Technology Research Laboratory, Electronics and Telecommunications Research Institute, Daejeon 305-350, Republic of Korea. chuh@etri.re.kr.
authors.forename: Chul
authors.initials: C
authors.lastname: Huh
authors.forename: Bong Kyu
authors.initials: BK
authors.lastname: Kim
authors.forename: Byoung-Jun
authors.initials: BJ
authors.lastname: Park
authors.forename: Eun-Hye
authors.initials: EH
authors.lastname: Jang
authors.forename: Sang-Hyeob
authors.initials: SH
authors.lastname: Kim