3:15 PM - 3:30 PM
[16p-A24-8] Evaluation of SiNx-Si Interface using a Laser Terahertz Emission Microscope (LTEM)
Keywords:solar cell, terahertz wave, passivation layer
We measured THz peak amplitude using laser terahertz emission microscope (LTEM) and capacitance-voltage(C-V) characteristics to evaluate the passivation surfaces of n-Si wafers with SiNx layers. We formed a SiNx layer on the top surface of n-Si. ITO electrode on the top surface and Al electrode at the bottom are evaporated, then the sample connected to a DC voltage source to tune the surface band bending of the silicon while allowing for the LTEM measurements. The voltage shift from C-V curve to THz peak amplitude is observed, but the shapes of THz peak amplitude and C-V curve showed good correlation. LTEM has been shown to be a diagnostic and mapping tool for surface passivation quality of various layers used in solar cells.