MEMS electron-transparent membranes made of low-stress silicon nitride are widely employed in electron microscopy. However, this material has limited resistance to electron beams. We therefore developed a layer of LPCVD SiC. Our layer is amorphous, uniform, continuous, low-stress, and has extremely low etch-rates in common wet etchants. As free-standing electron transparent window, it demonstrates a resistance to electron beam damage 3 times higher than low-stress LPCVD silicon nitride. Our SiC layer could be advantageously employed in other MEMS devices, especially those operating in harsh environments, and in applications where high etching selectivity is required.