Burra Mahesh Burra, There's someone on ResearchGate who found similar errors. His names is Fakhreddin Amirhosseini. He seems to be working in robotics. I can't tell if he's in school or working there. Regardless he might have ideas. See this link: https://www.researchgate.net/post/How_to_plot_the_Spectral_Response_of_a_semiconductor_device_in_Silvaco_Atlas_Simulation