Аннотация:A microfocus X-ray source based on a femtosecond ytterbium-doped fiber laser with a maximum pulse energy up to 20µJ and a repetition rate more than 100 kHz has been designed. In the scheme of tightly focusing onto the surface of a rapidly rotating copper disk, the use of the pulse burst mode and increase in repetition rate to 170 kHz provided a photon yield of 108 photons/s in 2π at a spectral brightness of 1.5 × 1011 photons/(s mm2 mrad2) (0.1% BW). The size of the designed source does not exceed 5 µm.