Field-emission cold-cathode el source for a microscale ion trap mass spectrometer
A cold-cathode electron impact ionization source based on field emission from an array of diamond-coated silicon whiskers is described. The source is coupled to a microscale ion trap mass spectrometer (r0 = 0.50 mm, z0 = 0.50 mm). An electron beam of 250 nA could be obtained through the 0.45-mm diameter opening in the end cap electrode.