Homoepitaxial growth of Si-doped β-Ga₂O₃ films on semi-insulating (100) β-Ga₂O₃ substrates by metalorganic chemical vapor deposition (MOCVD) is studied in this work. By appropriately optimizing the growth conditions, an increasing diffusion length of Ga adatoms is realized, suppressing 3D island growth patterns prevalent in (100) β-Ga₂O₃ films and optimizing the surface morphology with [010] oriented stripe features. The slightly Si-doped β-Ga₂O₃ film shows smooth and flat surface morphology with a root-mean-square roughness of 1.3 nm. Rocking curves of the (400) diffraction peak also demonstrate the high crystal quality of the Si-doped films. According to the capacitance–voltage characteristics, the effective net doping concentrations of the films are 5.41 × 10¹⁵ – 1.74 × 10²⁰ cm⁻³. Hall measurements demonstrate a high electron mobility value of 51 cm²/(V·s), corresponding to a carrier concentration of 7.19 × 10¹⁸ cm⁻³ and a high activation efficiency of up to 61.5%. Transmission line model (TLM) measurement shows excellent Ohmic contacts and a low specific contact resistance of 1.29 × 10^-4 Ω·cm² for the Si-doped film, which is comparable to the Si-implanted film with a concentration of 5.0 × 10¹⁹ cm⁻³, confirming the effective Si doing in the MOCVD epitaxy.