Patent ID: 8887527
Filing Date: 2014-11-18
Classification: B81B,B81C,C03B

Abstract:
1. A foaming process for preparing wafer-level glass micro-cavities, comprising the following steps: step 1: etching silicon trenches with 10-200 μm depth and a depth-width ratio of <2 on a silicon wafer through a silicon micro-machining process, step 2: placing powder of a high-temperature outgassing agent in the silicon trenches, step 3: bonding a piece of Pyrex7740 glass wafer to the silicon wafer by anodic bonding in air or vacuum, such that the silicon trenches form sealing cavities, step 4: heating up in air the silicon wafer bonded with the Pyrex7740 glass wafer to 820° C.-890° C., and holding for 3˜5 min, so that the high-temperature outgassing agent releases gas due to heat and thereby positive pressure inside the sealing cavities is created, and the molten glass corresponding to the sealing cavities deforms and thereby glass micro-cavity structures corresponding to the silicon trenches are formed on the glass wafer, and cooling down to obtain wafer-level glass micro-cavities.