Patent ID: 6809469
Filing Date: 2004-10-26
Classification: H01J

Abstract:
An electron beam apparatus comprising a hermetic container which includes an electron source having electron emission devices and targets exposed to the electrons emitted from said electron source and further comprising a first member within said hermetic container,wherein the value of the incident angle multiplication coefficient of secondary electron emission coefficient m0, which is a parameter of the following formula: Î´Î¸Î´0=1-{1-m0&it;cos&it;â€ƒ&it;Î¸1+(m1)-1Ã—(m0&it;cos&it;â€ƒ&it;Î¸)m2}exp&af;(-m0&it;cos&it;â€ƒ&it;Î¸)1-{1-m01+(m1)-1Ã—m0m2}&it;exp&af;(-m0)Ã—1cos&it;â€ƒ&it;Î¸General&it;â€ƒ&it;Formula&it;â€ƒ&it;(1)is 10 or less,when obtaining it from the value of secondary electron emission coefficient measured under the conditions that incident energy is 1 keV and incident angle is 0 degree as well as the values measured under the conditions that incident energy is 1 keV and incident angles &thgr; are 20, 40, 60 and 80 degrees by conducting a regression analysis by the least square method in said general formula (1), provided that the second electron emission coefficient of the surface of said first member has two incident energies which satisfy the second electron emission coefficient &dgr;=1 under the vertical incident conditions, and that when the larger energy of the above two energies satisfying &dgr;=1 is referred to as a second cross-point energy, the secondary electron emission coefficients for the primary electrons whose incident angles are &thgr; and 0 degrees are represented by &dgr;&thgr;, &dgr;0, respectively, and m1, m2 have the values m1=0.68273 m2=0.86212, respectively, in the incident energy equal to or lower than the second cross-point energy.