Preparation of ultrathin tritium source by using the ion implantation

The preparation of tritium source of large area and high activity by using the ion implantation for measuring the rest-mass of neutrino was described, in which,the tritium is implanted into the carbon coating on a microcrystalline glass plate. In this way, the tritium source was then successfully prepared with its stripe-width of 0.2mm, area of 40��30mm2, activity of 20MBq/cm2, activity distribution uniformity of 95%, tritium implantation depth of 2 ��g/cm2 and the tritium release rate of 4��102Bq/h.