Abstract:
Intended is to provide an electron radiation cathode of a high brightness, low energy dispersion and a long lifetime. Also intended is to provide a diamond electron radiation cathode, which can be sufficiently stably gripped, which is sharpened at its leading end and which is improved in a field intensity. The diamond electron radiation cathode (110) is characterized in that it is divided into at least three regions, that is, a leading end region (203) for irradiating a column-shaped leading end with electrons, a trailing end region (201) confronting in the longitudinal direction and adapted to be gripped, and a radially thinned intermediate region (202), in that the trailing end region has a sectional area of 0.2 mm2, in that the leading region has a sharpened leading end, and in that the radially thinned intermediate region has a sectional area of 0.1 mm2 at most.
Abstract:
단결정 다이아몬드(10)는, 표면(10a)을 갖는다. 단결정 다이아몬드(10)에서는, 단결정 다이아몬드(10)의 투과율이 최대인 부분 및 상기 투과율이 최소인 부분을 포함하며, 1변의 길이가 0.2 ㎜인 복수의 정사각형 영역(20a)이 연속한 측정 영역(20)을 표면(20a)에 있어서 규정하고, 또한, 복수의 정사각형 영역(20a)의 각각에 있어서의 투과율의 평균값을 측정한 경우에 있어서, 하나의 정사각형 영역(20a)에 있어서의 투과율의 평균값을 T 1 로 하며, 상기 하나의 정사각형 영역(20a)과 인접하는 다른 정사각형 영역(20a)에 있어서의 투과율의 평균값을 T 2 로 하였을 때에, 측정 영역(20)의 전역에 걸쳐 ((T 1 -T 2 )/((T 1 +T 2 )/2)×100)/0.2≤20(%/㎜)의 관계가 만족된다.
Abstract:
A process in which a low-resistivity phosphorus-doped epitaxial diamond thin film having a resistivity at 300 K of 300 7cm or lower is grown on the main plane of a {111} single crystal substrate under such conditions that a raw-material gas has a phosphorus atom/carbon atom ratio of 3% or higher, characterized in that the main plane has an off angle of 0.50° or larger. Also provided is a diamond single crystal having a low-resistivity phosphorus-doped epitaxial diamond thin film, characterized in that the surface of the thin film has an off angle of 0.50° or larger with the {111} plane and that the low-resistivity phosphorus-doped epitaxial diamond thin film has a resistivity at 300 K of 300 7cm or lower.