Ultra-precision diamond grinding of vapour cells in silicon for quantum technology

Abstract We present the use of computer numerical control (CNC) diamond machining with an ultra-precision milling/grinding system to manufacture alkali vapour cells at wafer-scale for quantum technologies. Fabricated cells were loaded with rubidium, bonded under vacuum, and tested in an absorption spectroscopy setup. The results are comparable to similar cells produced via chemical wet etching. Compared to a cleanroom-based chemical etching process, CNC machining can offer a cheaper, more environmentally sustainable route to manufacture of these devices. It also enables rapid prototyping and adjustments to design, whilst simultaneously allowing for scaling to volume production.