We used two-step molecular beam epitaxial (MBE) growth to integrate monolithically single and double vertical-cavity structures on a wafer. This technique is useful for making a single vertical-cavity surface-emitting laser-thyristor with a low threshold and a double vertical-cavity heterojunction phototransistor with both a high responsivity and a large spectral bandwidth. Regrowth on a patterned distributed Bragg reflector after thermal desorption of a passivating GaAs layer resulted in the laser in the single-cavity section having a threshold current density of 1.0 kA/cm(2), which is comparable to that of one grown by conventional one-step MBE. Controlling thickness to within +/-0.3% resulted in the regrown double-cavity section having a bandwidth of 5 nm.