研究期間：10108~10207;In this proposal, Si quantum dot (Si-QDs) based heterojunction solar cells will be fabricated using electron cyclotron resonance chemical vapor deposition (ECR-CVD) combined with post-annealing process. Si-QDs embedded in dielectric matrix show the bandgap widening effect as the Si-QDs size reduces below the Bohr radius since quantum confinement effect (QCE) is dominant in this scale. Therefore, Si-QDs embedded in a dielectric film could be a potential candidate as an emitter material of solar cells due to its higher light transmittance. For this purpose, introduction of dopants into Si-QDs has to be developed. However, fabrication of doped Si-QDs is very challenging due to self-purification effect, which is an intrinsic thermodynamics mechanism whereby impurities are expelled. During the project’s first year, we will develop B or P doped Si- QDs embedded in SiOx films and investigate their optical and electrical properties. In addition, hydrogen plasma will be used to passivate Si dangling bonds within these films. In the second year, we will focus on the fabrication of Si-QD based heterojunction solar cells. The interfaces between metal electrodes and SiOx and between SiOx and Si wafer will be modified to lower interface resistivity for higher current transport. Finally, we expect to obtain a solar cell with efficiency higher than 15%.
