Title :
Improvement of Light Trapping in a-Si:H-Based Solar Cells by Inserting a ZnO/LiF Double Interlayer
Author :
Ji-Hwan Yang ; Seung Yeop Myong ; Koeng Su Lim
Author_Institution :
Dept. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol., Daejeon, South Korea
Abstract :
We develop a zinc oxide (ZnO)/lithium fluoride (LiF) double interlayer for effective light trapping in p-i-n-type hydrogenated amorphous silicon (a-Si:H)-based solar cells with a 200-nm-thick intrinsic a-Si:H absorber. The spectral response of the fabricated solar cell with an n-type a-Si:H (n-a-Si:H)/ZnO/LiF/aluminum back structure was significantly enhanced in the wide wavelength range of 500-750 nm because of the refractive index grading, reduced plasmonic absorption, and efficient tunneling of photogenerated electrons through the ultrathin LiF interlayer, resulting in the significant enhancement of the short-circuit current by 21.6%. Consequently, the conversion efficiency is improved by 13.3%.
Keywords :
absorption; elemental semiconductors; plasmonics; refractive index; silicon; solar cells; Si:H; ZnO-LiF; electrons; hydrogenated amorphous silicon; light trapping; photogenerated electrons; plasmonic absorption; refractive index grading; short-circuit current; solar cells; wavelength 500 nm to 750 nm; zinc oxide-lithium fluoride double interlayer; Absorption; Amorphous silicon; Charge carrier processes; Photovoltaic cells; Plasmons; Zinc oxide; ZnO/LiF interlayer; amorphous silicon; solar cells;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2013.2287885
