When primary electrons hit the surface of the chunnel, secondary electrons are generated, which make the electron distribution at the exit hole of the chunnel more uniform.
When primary electrons hit the surface of the chunnel, secondary electrons are generated, which make the electron distribution at the exit hole of the chunnel more uniform.
当初始电子碰撞绝缘壁时，会产生二次电子，而二次电子能改善电子在通道出口处的电子能量分布的均匀性。