This work attempts to correlate the plasma density and RF harmonic profiles with respect to the pressure (at 13.56, 27.12 and 40.68 MHz) with the stochastic and ohmic power absorption mechanisms in a Capacitively Coupled Discharge (CCD), over a wide pressure range (0.6–1000 mTorr). Diagnostics include calibrated capacitive probe, compensated Langmuir Probe (LP) and uncompensated floating LP for measuring plasma parameters and RF signals. Pressure profiles of stochastic and ohmic powers, P _Stoch and P _Ohm (at 13.56 MHz) are obtained from their ratio (ξ) and the power absorbed by the electrons. Normalized profiles of an effective power (∼ ρ : pressure dependent parameter) are tuned to reproduce closely the normalized plasma density profiles from which relative contributions of stochastic/ohmic mechanisms are determined. It is shown that up to ≈30 mTorr, plasma production is stochastic while beyond that both methods contribute jointly. The RF harmonic profiles can be analysed similarly. Higher harmonics produced by the intrinsic nonlinearity of the stochastic process should appear most clearly in the plasma at low pressures where the latter operates alone. On the other hand, the fundamental RF voltage that is always present in the plasma, can also produce higher harmonics at the probe tip by driving the nonlinear probe sheath. Thus, the harmonics produced directly by the stochastic nonlinearity are inextricably mixed up with those arising due to the probe sheath. Significantly, one may conclude therefore that it is not possible to investigate the stochastic mechanism of power absorption by a study of its harmonics when the latter are measured using invasive probes.

这项工作试图将与压力（13.56、27.12 和 40.68 MHz）相关的等离子体密度和 RF 谐波分布与电容耦合放电 (CCD) 中的随机和欧姆功率吸收机制相关联，在很宽的压力范围内 (0.6 –1000 毫托）。诊断包括校准电容探头、补偿朗缪尔探头 (LP) 和未补偿浮动 LP，用于测量等离子体参数和射频信号。随机功率和欧姆功率的压力分布P _Stoch和P _Ohm（在 13.56 MHz 下）从它们的比率 ( ξ ) 和电子吸收的功率中获得。有效功率的归一化曲线 (∼ ρ: 压力相关参数) 被调整以精确再现归一化的等离子体密度分布，从中确定随机/欧姆机制的相对贡献。结果表明，在高达 ≈30 mTorr 时，血浆产生是随机的，而超过这两种方法共同贡献。可以类似地分析 RF 谐波分布。由随机过程的固有非线性产生的高次谐波应该在低压下的等离子体中最清楚地出现，而后者单独运行。另一方面，始终存在于等离子体中的基波射频电压也可以通过驱动非线性探头鞘在探头尖端产生高次谐波. 因此，由随机非线性直接产生的谐波不可避免地与由探头护套引起的谐波混合在一起。显著，可以因此结论是不能够通过其谐波的研究，当后者使用侵入式探针测量，调查功率吸收的随机机制。