A fabrication process for three-dimensional micro-tubes was developed using existing readout circuit electrode growth equipment and direct-write photolithography system. In the preparation process, the three-dimensional micro-tubes were first prepared on the surface of the readout circuit. The indium bumps were grown on the HgCdTe chip, and then flip-chip bonding was used to achieve interconnections between the 1k×1k array HgCdTe chip with 7.5 μm pitch and the readout circuit. The controllable parameters include metal growth angle, growth rate, thickness, and metal type, etc. It is found that the height of the three-dimensional micro-tubes with 7.5 μm pitch prepared by this process can reach 3.8 μm, the height non-uniformity is less than 3%, and it can withstand the pressure of 7.6×10^-5 N. The application of the three-dimensional micro-tubes reduces the requirements for the flatness of HgCdTe chips and the precision of interconnection equipment in the flip-chip bonding process, significantly improving the yield of interconnected infrared detectors with 7.5 μm pitch.