Epson utilizes a photolithographic process called QMEMS to create uniformly shaped miniature crystal chips which are used in sub-miniature crystal units and crystal oscillators. As an example, for the same size 2.0 mm x 1.6 mm crystal unit, the QMEMS process provides outstanding temperature characteristics with minimal frequency variation compared to the conventional mechanical processing technique. As a reference, the QMEMS symbol is indicated next to products utilizing this technology in this presentation.