A Langmuir probe has been used to investigate electron heating mechanisms in a capacitively coupled oxygen discharge over a wide pressure range (50–800 mTorr) at a fixed applied power (200 W). Evidence presented here from experimentally obtained electron energy distribution functions (EEDFs) illustrates discharge transition from a collisionless (stochastic) to a collisional (Ohmic) dominant regime with increasing oxygen pressure. The discharge exhibited a bi-Maxwellian EEDF in the collisionless regime, dominated by stochastic heating whereas Druyvesteyn-like EEDFs were exhibited in the collisional dominant regime. Moreover, in the transition between these two regimes, parameters such as electron density, effective electron temperature and electron-neutral collision frequency exhibited significant variations.

中文翻译：

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电容耦合射频氧放电中电子加热模式的实验研究

Langmuir探针已被用于研究在固定施加功率（200 W）的宽压力范围（50–800 mTorr）中的电容耦合氧放电中的电子加热机理。从实验获得的电子能量分布函数（EEDF）得出的证据表明，随着氧气压力的升高，放电从无碰撞（随机）到碰撞（欧姆）占主导地位的过渡状态。放电在无碰撞状态下表现出双麦克斯韦式EEDF，由随机加热控制，而在碰撞主导状态下则表现出类似Druyvesteyn的EEDF。而且，在这两种状态之间的过渡中，诸如电子密度，有效电子温度和电子-中性碰撞频率的参数表现出显着的变化。