Disclosed is a method for manufacturing a diamond film of electronic quality at a high rate using a pulsed microwave plasma. The plasma that has a finite volume is formed near a substrate (in a vacuum chamber) by subjecting a gas containing at least hydrogen and carbon to a pulsed discharge. The pulsed discharge has a succession of low-power states and of high-power states and a peak absorbed power P.sub.C, in order to obtain carbon-containing radicals in the plasma. These carbon-containing radicals are deposited on the substrate in order to form a diamond film. Power is injected into the volume of the plasma with a peak power density of at least 100 W/cm.sup.3, while maintaining the substrate to a substrate temperature of between 700.degree. C. and 1000 .degree. C.