Method of encapsulating a microelectronic device by a getter material

A method of encapsulating a microelectronic device arranged on a substrate, comprising at least the following steps:

• a) formation of a portion of sacrificial material covering at least one part of the microelectronic device, the volume of which occupies a space intended to form at least one part of a cavity in which the device is intended to be encapsulated,
• b) deposition of a getter material layer, a rear face of the getter material in the getter material layer covering at least one part of the portion of sacrificial material,
• c) formation of at least one orifice through at least a first cover comprising the getter material layer and a first hermeticity layer above the getter material layer, thereby forming an access to the portion of sacrificial material,
• d) elimination of the portion of sacrificial material via the orifice, thereby forming the cavity in which the microelectronic device is encapsulated and such that at least a portion of the rear face of the getter material is exposed in the cavity and said rear face of the getter material forms an entirety of a principal upper wall of the cavity, except for a portion occupied by the orifice, without an intervening material between the getter material layer and the cavity, and able to absorb gas in the cavity, and
• e) sealing of the cavity.