The beam quality of the high power master oscillator and power amplifier (MOPA) system is mainly determined by the seed of master-oscillator which needs careful optical design and precise alignment. To suppress the high amplified spontaneous emission (ASE) level in the XeCl gain medium and extract the deposited energy efficiently, a higher seed energy is needed. A master-oscillator integrated with seed generation and self-amplification which meets the MOPA system requirement is described. A grating is used to form a self-alignment resonator to obtain narrow line-width and small divergence seed using a discharge-pumped XeCl excimer laser. To get enough energy, the seed is further amplified by another two-pass amplifier in the same device. The alignment of the self-collimated grating resonator is the key issue to obtain the designed parameters like pulse energy and narrow line-width. With the help of single transverse mode He-Ne laser and a preliminary plane-parallel cavity inserted before the grating, expectedd experimental results are obtained and the measured seed laser pulse energy and intensity distribution at different position are given. After removing the plane-parallel cavity, the seed pulse energy is about 8 mJ from the grating cavity and the energy is boosted to 60mJ with additional double pass amplification and extender telescrope. And the line-width of the seed pulse is 0.6 cm-1, near the diffraction limit, and meets the demand of the following amplification.