Development of silicon nanowires with optimized characteristics and fabrication of radial junction solar cells with < 100 nm amorphous silicon absorber layer. (February 2020)

• Record Type: Journal Article
• Authors: Ahmed, Nafis; Ramasamy, P.; Bhargav, P. Balaji; Rayerfrancis, Arokiyadoss; Chandra, Balaji
• Is Part Of: Materials science in semiconductor processing. Volume 106(2020)
• Publication Date: 2020-02
• Subjects: Silicon nanowires -- VLS mechanism -- Tin catalyst -- PECVD -- Solar cells -- Radial junction; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2019.104778
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: We report the growth and characterization of Silicon nanowires (SiNWs) via the VLS mechanism with two different tin (Sn) catalyst thicknesses of 2 and 4 nm at 400 and 500 °C by PECVD. The effect of catalyst thickness, plasma power density and growth temperature on the morphology of nanowires is investigated. The structural morphology of the grown NWs is analyzed using FESEM and HRTEM. It has been inferred the density, diameter and length of NWs can be effectively controlled by PECVD process parameters. HRTEM analysis demonstrates a highly crystalline silicon core with (111) plane as preferred orientation. Grazing incidence X-ray diffraction spectra of the samples prepared at two different temperatures confirmed the (111), (220) and (311) plane orientation of the grown NWs. Raman spectra of the SiNWs grown on glass substrate shown broadened spectrum centering at 508 cm -1 confirming the crystalline nature of NWs core surrounded with dense layer of a-Si. Optimized parameters are used to fabricate radial junction solar cells and the effect of catalyst thickness on the performance is explored. Short circuit current density of 13.53 mA/cm 2 and open circuit voltage of 0.82 V for 0.25 cm 2 solar cell having power conversion efficiency of 6.66% is obtained.