Modeling the optical and electrical response of nanostructured III–V solar cells

Abstract

Concentrator Photovoltaics (CPV) have emerged as a potential alternative energy source due to a favorable balance between cost and efficiency. In contrast to traditional flat panel systems, CPVs result in cheaper fabrication costs since a bulk of the pricey crystalline solar cell is replaced with less expensive light collection and concentrator materials. However, in order to remain competitive with other energy technologies, CPV systems require core solar cells with both high efficiencies and low temperature coefficients. To address the previous need, incorporating nanostructures, such as quantum wells (QW) and quantum dots (QD), into III-V solar cells has been proposed as a potential route towards achieving efficiencies well exceeding 50% under concentration. Hence, vital to the design process of this particular class of solar cells is the ability to accurately calculate nanostructure properties critical to the operation of CPV devices. Here, we have developed a modeling routine using the physics based software Crosslight to systematically study how quantum effects influence the performance of photovoltaics. In particular, this methodology can be applied to study how nanoscale variables, including size, shape and material compositions, can be used to tailor the electrical and optical properties at the device level. Finally, macro-level engineering of the nanostructures, such as the number of stacked layers as well as the position of these structures within the device, is explored in optimizing the overall device response.