The preparation required for micro components at the design stage carries through all the way to automated assembly. Because the tolerances are critical and diminishing to microns and sub-microns, the stack-up tolerances of the micro components and their design criteria are scrutinized and their method of manufacturing are also considered for long-term production. The mechanics of micro assembly and the testing, inspection, application knowledge are required for fully functioning specks of dust working collaboratively and repeatedly. Handling these components is a challenge requiring high speed automation capable of handling dust speck sized parts, in-line metrology and vision systems to insure form, fit, and function, and positional accuracy to sub-micron tolerances. These joining/assembly methods include:
- AVOIDANCE OF HANDLING- Combining geometry into the least number of parts in a micro assembly
- TWO-SHOT MICRO MOLDING/OVER-MOLDING- Two-shot molding (2 injection barrels of two different materials) injecting into a mold at two different locations or in the same location with a rotating mold
- LASER WELDING- Careful control of laser energy and power densities can be used to selectively clean and strip materials such as wires quickly and non-destructively.
- ULTRASONIC WELDING-Very tiny (70-100 um) weld beads are possible with custom low energy boosters and ultrasonic horns.
- SOLVENT BONDING-Appropriate solvents must be used that are compatible with the materials being solvent bonded, especially if the assembly is to be used as an implantable.
- STAKING- Crimping or staking is a very common practice to generate good seals for preventing costly fluids from escaping the micro vessel.