The conversion of light into excited electrons is a fundamental process in many technologies. Common examples include the photogeneration of carriers in photovoltaics and photodetectors or exciton generation in photocatalysis. A more specific example is the conversion of light into THz radiation in photoconductive antenna (PCA) devices. PCA devices integrate micron-scale electrode antennas with a layer of semiconductor in the gap between two electrodes under an applied bias. The semiconductor generates transient conductive behavior upon the absorption of an ultrafast laser pulse or continuous wave excitation. As a result, a pulse of broadband THz radiation is emitted from the PCA device, which can be used for a variety of analytical and imaging applications. Commonly used materials such as GaAs are direct gap semiconductors that absorb a large fraction of the incident illumination in a thin film, generally hundreds of nanometers thick. However, films with this thickness also absorb the generated THz and limit the power conversion efficiency of the device. Two-dimensional (2D) materials such as transition metal dichalchogenides (MoS2, WSe2) or black phosphorous are of potential interest to PCA devices due to the demonstrated thickness-dependent optical properties and tailorable defect generation. The efficiency and quantum yield of the optical-to-THz process in the PCA device is proportional to the optical absorption. A consequence of reducing the thickness of the absorber layer is that optical absorption decreases exponentially with thickness. Hence, there is a technical impetus to develop strategies to increase light absorption in PCA devices based on ultra-thin film semiconductor light absorbers.