Efficient laser-diode pumped picosecond self-Q-switched all-ceramic composite Yb:YAG/Cr(4+):YAG microchip lasers with 0.72 MW peak power has been developed. Lasers with nearly diffraction-limited beam quality (M(2) < 1.09), oscillate at stable single- and multi- longitudinal-modes due to the combined etalon effects in the Yb:YAG and Cr(4+):YAG parts of its binary structure.