Vacuum pump age effects by the exposure to the corrosive gases on the Cr etch rate as observed using optical emission spectroscopy in an Ar/O2/Cl2 mixed plasma

GaN LEDs fabricated using SF 6 plasma RIE

“…Our method provides a number of advantages. First, the use of conventional RIE and less corrosive fluorine gas not only reduces the production cost but also lowers the risk of corrosion in the RIE chamber and corrosive gas hazards [18–20]. Second, the etching rate for our LED arrays with substrates varies from 2–25 nm/min, which is significantly higher than the RIE etching methods reported by other groups [27, 34, 40].…”

“…Other specialised plasma etching techniques have been reported, such as reactive ion beam etching and chemically assisted ion beam etching with Cl 2 and BCl 3 as reactive gasses [17]. Although ECR‐RIE, ICP‐RIE, and ion beam etching have a unique ability to control the ion flux and ion energy separately, these techniques usually involve corrosive chlorine, chlorine mixtures, and chlorine‐based halocarbons based plasmas [18, 19] that damage the vacuum system and requires expensive reactive chamber and specific filtration system [20] in contrast with less corrosive SF 6 , CH 4 , Ar, and H 2 based plasmas [19]. In addition, hydrogen diffusion in GaN during ECR‐RIE can create electrically neutral complexes with dopants [21].…”

Cause analysis of the faults in HARC etching processes by using the PI‐VM model for OLED display manufacturing

“…Measured b were distributed in the very narrow range of 0.715 to 0.775. This is a very small change according to the value of b itself, but the 0.05 change of shape factor corresponded to a tens of % change in the high‐energy tail (region over the effective threshold energy of dissociation or ionization of the process gases, >10 eV in general) for the fixed T e,eff . In the huge mass production system, a detailed variation of the plasma is caused by the electron impact collisions, which govern the energy relaxation characteristics of the high‐energy electrons.…”

“…This analyzed mechanism of the process fault for the 21 glasses leads pay attention to the very small change in the etcher. For example, the instability of the He flow, which cools down the backside of the glass on the ESC, and minor deviation of the exhaustion efficiency by the abrasion or corrosion of the rotating blades in the vacuum pumps, can become a significant trigger to transfer the state of the HARC etching process …”

“…For the change of EEDF tail with a level of 10 −3 of total EEDF area, the induced variation of radical generation rate can be high as the tens of %. This microscopic variation of the plasmas is hard to detect in terms of the plasma temperature T e with the assumption of the Maxwellian distribution . However, the HARC etching processes have very small margins to the faults in the processes; thus, this microscopic change is required to be sensed for the mass production management.…”