SiO2 Dielectric Micro-Pattern Layer for Solar Cell Application

Micro-patterns were created in a silicon dioxide (SiO2) dielectric layer (called SiO2 dielectric micro-pattern layer) via the photolithography and dry etching techniques. The SiO2 dielectric micro-pattern layer was utilized as an antireflection layer for solar cell application. The influences of structure of micro-pattern on the optical and electrical characteristics of solar cell were also investigated in detail. An improved performance of the GaAs solar cell by combination of antireflection coating layers and micro-pattern was observed. An enhancement in short circuit current density of 7.5% and conversion efficiency (about 1.2% absolute) were achieved in a cell coupling with the SiO2 dielectric 4 μm period micro-pattern layer compared to those of a reference cell. The influences of the SiO2 dielectric micro-pattern layer on other performance characteristics such as open circuit voltage and fill factor were not clearly observed. Light beam induced current measurement was also carried out to indicate the contribution of the light trapping and light scattering effects on the cell performance.