National Aeronautics and Space Administration

Glenn Research Center

Nathan McKay


The quantum dot nipi device is a promising approach to create ultra-high efficiency solar cells. One step required for the development of this device is an anisotropic etch process for v-grove formation. Anisotropic wet etching of GaAs was demonstrated using processes developed at Glenn Research Center. Photolithography was used to deposit a pattern of photoresist on a GaAs substrate. Samples of this substrate were then etched using a 2:1:50 solution of NH4OH:H2O2:H20. Samples were placed in the etchant solution for different periods of time to experimentally determine an etch rate of 613 nm/min. Anisotropism was confirmed through imaging of the etched features. The processing chemicals and equipment available at the facility were evaluated for future work developing the quantum dot nipi device.