Wafer-level capping and sealing of heat sensitive substances and liquids with gold gaskets

•Method for encapsulation of liquids with high confinement grade.•Method for packaging heat and/or vacuum sensitive devices at room-temperature and ambient pressure.•Method is presented for liquid sealing and for an optical gas sensor package.•Use of microfluidic channels for bubble-free wafer-level underfill application on wafer stacks with very small gap.•Sealing mechanism is based on plastic deformation of gold gaskets at room temperature. This paper reports on a novel wafer-level packaging method employing gold gaskets and an epoxy underfill. The packaging is done at room-temperature and atmospheric pressure. The mild packaging conditions allow the encapsulation of sensitive devices. The method is demonstrated for two applications; the wafer-level encapsulation of a liquid and the wafer-level packaging of a photonic gas sensor containing heat sensitive dye-films.