Abstract: In the process of developing a national military standard hybrid integrated circuit product, the eutectic sintering penetration rate of the ceramic substrate directly affects the important parameters such as the noise figure and gain of the product. In this paper multiple sets of evenly-integrated, independently weighted and invertedly-locked integrated graphite fixtures are designed, with which the eutectic sintered carrier limit can be realized. When inverted, the multiple sets of heavy needles hang in the air, not pressed; when placed normally, the multiple sets of heavy needles hang down automatically and the sheet is evenly weighted and pressed. The uniform eutectic sintering is finally completed. The graphite fixture developed by this design method can effectively solve the problem of high offset and void ratio of the substrate. As a result, the grounding performance of the circuit unit is ensured, the batch development technology bottleneck of the national military standard hybrid integrated circuit product is broken through and meanwhile the quality consistency level of batch products is improved. The test results of penetration rate and important indicators verify the feasibility and effectiveness of this design method.