Patent attributes
A method for manufacturing a cover assembly including a transparent window portion and a frame of gas-impervious material that can be hermetically attached to a micro-device package base to form a hermetically sealed micro-device package. First, a frame of gas-impervious material is provided, the frame having a continuous sidewall defining a frame aperture there through. The sidewall includes a frame seal-ring area circumscribing the frame aperture. A sheet of a transparent material is also provided, the sheet having a window portion defined thereupon. The window portion has finished top and bottom surfaces. A sheet seal-ring area is prepared on the sheet, the sheet seal-ring area circumscribing the window portion. The frame is positioned against the sheet such that at least a portion of the frame seal-ring area and at least a portion of the sheet seal-ring area contact one another along a continuous junction region that circumscribes the window portion. The frame is pressed against the sheet with sufficient force to produce a predetermined contact pressure between the frame seal-ring area and the sheet seal-ring area along the junction region. The junction region is heated to produce a predetermined temperature along the junction region. The predetermined contact pressure and the predetermined temperature are maintained until a diffusion bond is formed between the frame and sheet all along the junction region.
