For the first time as-grown laser scattering tomography defects (LSTD), twins, was observed directly in the Si water with transmission electron microscopy (TEM).The shape of the grown-in LSTDs, estimated from the TEM images, were octahedral and tetrahedral, with sidewalls lying in the {111} plane. The size of grown-in LSTDs are approximately 100 nm.The oxygen concentration inside the grown-in LSTD was close to the detection limit of TEM-EDX Selective Dry Etching of Ill-V Nitrides in C12/Ar,