Sealing of silicon-glass microcavities with polymer filling

Investigation of hermetic sealing of selected polymers in silicon-glass microcavities has been presented. The anodic bonding method has been adapted for hermetic encapsulation of the polymer in microcavity. According to standard conditions of the anodic bonding process (temperature: 400°C, voltage: 1000 V), the main challenge was the significant reduction of temperature in order to avoid degradation of the polymer. An analysis of the influence of reduced temperature and oxygen-free atmosphere on bond quality has been done. Proper parameters of the anodic bonding process enabling good and hermetic encapsulation of the polymer in the microcavity as well as optimal polymer treatment have been elaborated. Studies have shown that the closure of high density polyethylene in microcavity by anodic bonding process at a temperature reduced to 340°C is possible. This procedure will be used for the fabrication of main elements for a new family of high radiation MEMS sensors.