## 4 Result and Discussion
### Discussion  
The electron density in the experiment shows a similar tendency. The tendency of electron density according to radial position is similar, and the difference lies only in the tendency of density to increase as pressure increases. When comparing the electron density tendency at a lower pressure of 3 mTorr and a higher pressure of 150 mTorr beyond the experimental pressure range, the experiment in the paper shows an intermediate tendency [39]. The main cause of this difference is the electron energy relaxation length  
Figure 14: Pressure variation energy influx with Equation (1) from ETSW. Figure 13: Pressure variation energy influx obtained from 12-inch equipment sensor data. Figure 15: Bias power variation energy influx with Equation (1) from ETSW. and the variation in electron heating mechanism. At high pressures, collisional heating dominates and heated electrons near the plasma boundary lose energy through inelastic and e-e collisions in the skin layer before reaching the plasma bulk. Therefore, the RF power is mainly deposited in the skin layer near the plasma boundary, and the maximum plasma density occurs at the chamber boundary. However, at low pressures, non-local electron kinetics can explain the different tendency. Electrons heated by the vortex electric field can pass through the skin layer in a short time and acquire net energy. They then traverse the entire volume before losing energy. Additionally, due to ambipolar diffusion, the maximum plasma potential exists at the center of the discharge chamber, leading to maximum kinetic energy for electrons at the center. As a result, the region of maximum ionization occurs near the center of the chamber, where there is an absent or weak RF field. The electron temperature in the experiment shows a tendency to increase and then decrease once at the 15 mm position, except for the case of 30 mTorr. This difference is likely due to the variation in coil shape. Additionally, when comparing simulations and experiments with the same coil shape as the actual experiment, the differences in plasma potential distribution or electron temperature distribution can be observed [40]. The coil shape is determined by factors such as the coil thickness, the gap between coils, the number and the positioning of the coils. These elements can vary, potentially impacting the strength, the distribution of magnetic fields and the shape of the plasma source region. One of the plasma diagnostic sensors, OES, had limitations in measuring plasma parameters due to bias power variation among process parameters. Therefore, to derive plasma energy influx through OES, it is necessary to complement plasma parameters according to bias power variation using other diagnostic sensors. Energy influx values derived from 12-inch equipment using measurement sensors are at least twice as large as energy influx values derived from ETSW data and differ by up to five times. This is because the wafer temperature decreases due to the cooling effect of the ESC backside gas, which results in a difference between the energy influx value calculated in plasma bulk and the energy influx value calculated in ETSW. Additionally, there was a difference in the value of the bulk plasma parameter obtained by each measurement sensor. As a result, a difference in energy influx values was observed. The energy influx derived from the 6-inch equipment tends to gradually decrease towards the edge, while the ETSW energy influx tends to increase as it goes towards the edge. The wafer temperature in the wafer edge region can be increased by plasma and focus ring [41]. As a result, the ETSW sensor temperature increases further in the edge region than in the center region. In addition, the temperature difference increases, leading to the higher value of energy influx in the edge than in the center region. Thus, the increases in bias power and energy influx are similar for each radial position. Energy influx with center-to-edge bias power variation also exhibits a similar tendency.