| 摘要 |
<p>PURPOSE:To achieve high electron emission efficiency, by increasing the ratio of electron flow injected from N type semiconductor substrate to P type semiconductor layer. CONSTITUTION:P type semiconductor layer 22 of low resistance is formed on one surface of high resistance N type semiconductor substrate 21 while an ohmic electrode 25 is formed on the back face. An ohmic electrode 24 is formed on the other side face of P type semiconductor layer 22 than its face jointing with N type semiconductor substrate 21 while a thin layer 23 of alkali metal is formed on another portion of the this face. Then forward bias voltage is applied between said ohmic electrodes 24, 25. The majority of the bias current is injected as the electron flow into P type semiconductor layer 22 to increase the electron to be discharged into the vacuum.</p> |
