Facile preparation of hazy Ga-doped ZnO electrodes by atmospheric pressure plasma jet

Abstract

Increasing the optical path length without degrading optoelectronic properties of front electrodes of solar cells is promising to enhance the power conversion efficiency. This can be achieved by increasing the haze (H) of the electrode through texturing, while retaining high transmittance (Tt) and low sheet resistance (Rs). However, it is challenging to balance these properties simultaneously since they are mutually influenced. Here, we present a facile, low-cost, and single-run method of preparing gallium-doped zinc oxide (GZO) with high H (>25%), high Tt (>90% in the visible range, referenced to glass), and low Rs (6.62 Ω sq−1) using atmospheric pressure plasma jet. First, we increase the nozzle-substrate distance, or working distance (WD), to deposit a thin, rough GZO as a haze enhance (HE) layer and immediately deposit a standard GZO layer using the same apparatus. By tailoring the roughness of the HE layer using WD and scanning pitch, we successfully produce high-quality hazy GZO that have competitive figures of merit of 6.3 × 10−2 Ω−1 (referenced to the glass) and 2.1 × 10−2 Ω−1 (overall), and H = 25%. Also, unlike conventional methods, our approach does not require vacuum, etching, additional materials, or change of machine/tooling, which can significantly reduce the operational complexity.