Fig. 1. Patterning deposition process of micron sliver bumps. (a) Laser machined stainless steel mask; (b) mask pasted to DBC substrate; (c) PLD patterning deposition; (d) deposited micron sliver bumps

Fig. 2. Chip-DBC hot pressing bonding and its shear test. (a) Schematic of chip-DBC hot pressing bonding; (b) sintering temperature curve; (c) schematic of chip-DBC joint shear strength test

Fig. 3. Morphologies of Ag bumps by PLD patterning deposition. (a)(d)(g) SEM macroscopic morphologies of Ag bumps; (b)(e)(h) confocal three-dimensional morphologies of Ag bumps; (c)(f)(i) height variation curves of Ag　bump central sections under different mask thicknesses

Fig. 4. Cross-sectional morphologies of joint bonded with 500 μm feature size Ag bump array. (a) Whole sectional morphology; (b) morphology of single Ag bump; (c) (e) magnification of edge morphology of Ag bumps; (d) magnification of central-area morphology of Ag bumps

Fig. 5. Shear strength of joints bonded by different feature size Ag bumps

Fig. 6. Fracture morphologies of joints bonded by 500 μm feature size Ag bump array (DBC side). (a) Fracture occurred at Ag bump/DBC interface; (b) magnification of Ag bump/DBC fracture; (c) fracture occurred at Ag bump/Si chip interface; (d) magnification of Ag bump/Si chip fracture