Abstract: The present invention deals with an improved hermetic enclosure impervious to moisture, suitable for single or multiple chips. The enclosure is sealable at a low temperature safe for the enclosed electronic components. In particular, the enclosure employs matching direct bond copper surfaces on the substrate and on the cover which may be sealed together with solder. The cover is of a high temperature material which may be transparent. Transparent materials such as fused quartz, or garnet, or sapphire are suitable. The enclosure is economical at both small sizes and relatively large sizes; and the transparent cover material permits for optical signalling into the package.