Alkali metal vapor cell apparatus and process for making alkali metal vapor cells

A process for making a plurality of alkali metal vapor cells, the process comprising:

• providing a preform wafer comprising:
• a basal member;
• a cavity layer disposed on the basal member;
• a plurality of cell cavities disposed in the cavity layer and bounded by a cavity wall of the cavity layer;
• and
• a plurality of deposition cavities disposed in the cavity layer and bounded by the cavity wall of the cavity layer, such that each deposition cavity is adjacent to a cell cavity;
• disposing an alkali metal precursor in the deposition cavity of the preform wafer;
• providing a sealing wafer comprising a cover layer that comprises a blank;
• disposing the sealing wafer on the preform wafer so that a deposition surface of the sealing wafer faces and is in fluid communication with the deposition cavities of the preform wafer, such that the deposition cavities are individually isolated from fluid communication with other deposition cavities and cell cavities;
• subjecting the alkali metal precursor in the deposition cavities to a reaction stimulus;
• producing, from the alkali metal precursor, alkali metal vapor in the deposition cavities in response to subjecting the alkali metal precursor to the reaction stimulus;
• communicating, simultaneously in parallel, the alkali metal vapor from the deposition cavity to a deposition area on the deposition surface of the sealing wafer that covers the deposition cavity, such that each deposition area is local to an individual deposition cavity and physically separate from other deposition cavities and cell cavities;
• contacting the deposition area with the alkali metal vapor from the deposition cavity;
• producing, from the alkali metal vapor, an alkali metal condensate on the deposition area;
• separating the sealing wafer from the preform wafer;
• moving the sealing wafer laterally with respect to the preform wafer and aligning the deposition areas of the sealing wafer with the cell cavities of the preform wafer such that the individual deposition areas of the sealing wafer are in fluid communication with an individual cell cavity of the preform wafer in an aligned position and contacting the sealing wafer with the preform wafer in the aligned position to encapsulate the alkali metal condensate in individual deposition area in individual cell cavities;
• and
• bonding the sealing wafer to the preform wafer to make individually sealed alkali metal vapor cells in the preform wafer.