In theory, ceramics are excellent materials for packaging electronic products. Ceramics are hard, insulating and resistive, and biocompatible when implanted into the body. The problem that has always been faced with is that the fusion of ceramics often requires high heat, which will destroy electronic components. Recently, researchers have developed a new method to realize ceramic welding by ultrafast laser pulses at room temperature.

In order to lock them into the desired shape and keep them firm, the ceramic body needs to be fired in the furnace first. In most cases, this is possible, but if it is used as an electronic shield, the effect will not be so good.

Javier Garay, the lead author of the study, pointed out that "there is no way to encapsulate or seal electronic components in ceramics at present, because if you do so, you have to put the entire component in the stove, which will undoubtedly burn the entire electronic component."

So a team of scientists from the University of California, San Diego, and the University of California, Riverside, came up with a solution. Heat is still a necessary condition for welding ceramics, but researchers did not use high heat for the whole welding body, but used a process called ultra-fast pulsed laser welding, directly applied to the seam.

"By concentrating energy in specific places, we can avoid setting temperature gradients in the whole ceramic, so we can package temperature-sensitive materials without damaging them," Garay said.

Previously, similar ultrafast laser pulses have been used to weld materials that usually do not mesh well, such as transparent plastics or metals to glass. For this project, UC researchers have adjusted laser and ceramic materials to find the most effective set of parameters. Ceramic materials must have a certain degree of transparency, and the team must also find out the correct exposure time and the number and duration of laser pulses in order to obtain the best welding results.

Guillermo Aguilar, co-lead author of the study, said: "The most effective points for ultra-high-speed pulses are two picoseconds at a high repetition rate of 1 MHz and the number of medium total pulses. Only in this way can the melt diameter be maximized, the ablation of the material be minimized, and the timing cooling which is just suitable for the best welding.

In related experiments, the researchers successfully welded the transparent cylindrical cap to the inside of the ceramic tube. Then we use industry standard test to test it in vacuum, and find that it can keep the vacuum.

So far, the technology has only been used for small ceramic parts less than 2 centimeters (0.8 inches), but the team plans to try to expand the scale and also plan to weld different materials and shapes.

—— From OFweek