Semiconductor package with getter formed over an irregular structure

A method of processing a substrate, comprising:

• etching a first surface of the substrate, thereby forming a grass structure with a random arrangement of features on the first surface;
• depositing an adhesion layer on the grass structure;
• depositing a layer of getter on the adhesion layer to form a getter covered grass structure, the adhesion layer being operable to improve adhesion between the first surface and the layer of getter;
• and
• sealing the getter covered grass structure in a vacuum enclosure which contains microelectronic components, the getter covered grass structure being exposed to gas molecules within the vacuum enclosure, wherein the getter covered grass structure is used to remove gas molecules by absorbing the gas molecules.