Etching Characteristics of Low-k Dielectric Using C5H2F10 Liquefied Gas Plasma for Mitigating of Global Warming Potential

2021 ◽  
Vol 13 (9) ◽  
pp. 1764-1770
Author(s):  
Yeonsik Choi ◽  
Jongchan Lee ◽  
Younghun Oh ◽  
Hyun Woo Lee ◽  
Kwang-Ho Kwon

In this work, we studied the etch characteristics and dielectric constant change of SiOC thin films by plasma etching for the fabrication of nanoscale devices to evaluate the C5H2F10 as alternative etching gas. We performed plasma etching of SiOC films with inductively coupled plasma using the CF4+X+O2 mixed gas, where X = CHF3 and C5H2F10. Plasma diagnosis such as optical emission spectroscopy and double Langmuir probe measurements were carried. We analyzed the chemical compositions of residues on the etched SiOC film surface using X-ray photoelectron spectroscopy. After the process, contact resistance was measured using the transmission line method to analyze the degree of polymer on the surface of the silicon. Ellipsometry were used to evaluate the change in the dielectric constant of the thin film due to plasma exposure. It was confirmed that the etched profile was more vertical than that of the CHF3 gas plasma, and the increase in the dielectric constant of the SiOC thin film by C5H2F10 gas plasma is less than that of CHF3 gas plasma. These results confirmed that C5H2F10 gas was a powerful alternative to CHF3 gas in semiconductor processing for the fabrication of nanoscale devices.

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 906
Author(s):  
Chea-Young Lee ◽  
Young-Hee Joo ◽  
Minsoo P. Kim ◽  
Doo-Seung Um ◽  
Chang-Il Kim

Plasma etching processes for multi-atomic oxide thin films have become increasingly important owing to the excellent material properties of such thin films, which can potentially be employed in next-generation displays. To fabricate high-performance and reproducible devices, the etching mechanism and surface properties must be understood. In this study, we investigated the etching characteristics and changes in the surface properties of InGaZnO4 (IGZO) thin films with the addition of O2 gases based on a CF4/Ar high-density-plasma system. A maximum etch rate of 32.7 nm/min for an IGZO thin film was achieved at an O2/CF4/Ar (=20:25:75 sccm) ratio. The etching mechanism was interpreted in detail through plasma analysis via optical emission spectroscopy and surface analysis via X-ray photoelectron microscopy. To determine the performance variation according to the alteration in the surface composition of the IGZO thin films, we investigated the changes in the work function, surface energy, and surface roughness through ultraviolet photoelectron spectroscopy, contact angle measurement, and atomic force microscopy, respectively. After the plasma etching process, the change in work function was up to 280 meV, the thin film surface became slightly hydrophilic, and the surface roughness slightly decreased. This work suggests that plasma etching causes various changes in thin-film surfaces, which affects device performance.


Coatings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 637
Author(s):  
Wei-Kai Wang ◽  
Sung-Yu Wang ◽  
Kuo-Feng Liu ◽  
Pi-Chuen Tsai ◽  
Yu-Hao Zhang ◽  
...  

Yttrium oxyfluoride (YOF) protective materials were fabricated on sputter-deposited yttrium oxide (Y2O3) by high-density (sulfur fluoride) SF6 plasma irradiation. The structures, compositions, and fluorocarbon-plasma etching behaviors of these films were systematically characterized by various techniques. After exposure to SF6 plasma, the Y2O3 film surface was fluorinated significantly to form a YOF film with an approximate average thickness of 30 nm. X-ray photoelectron spectroscopy revealed few changes in the elemental and chemical compositions of the surface layer after fluorination, confirming the chemical stability of the YOF/Y2O3 sample. Transmission electron microscopy confirmed a complete lattice pattern on the YOF/Y2O3 structure after fluorocarbon plasma exposure. These results indicate that the SF6 plasma-treated Y2O3 film is more erosion resistant than the commercial Y2O3 coating, and thus accumulates fewer contamination particles.


2020 ◽  
Vol 12 (5) ◽  
pp. 641-646
Author(s):  
Jaemin Lee ◽  
Jihun Kim ◽  
Junmyung Lee ◽  
Hyun Woo Lee ◽  
Kwang-Ho Kwon

In this study, we evaluated the possibility of replacing existing perfluorocarbon gas with C7F14, which can be recovered in its liquid state from room-temperature air. We performed plasma etching of SiON films using the CF4 + X + O2 mixed gas, where X = CHF3, C4F8, or C7F14, and examined the etching characteristics of the films (e.g., etching rate, etching profile, and selectivity over Si). Using contact angle goniometry, atomic force microscopy, and X-ray photoelectron spectroscopy, we analyzed the physicochemical changes in the etched SiON film surface. Moreover, optical emission spectroscopy and double Langmuir probe measurements were carried out for plasma diagnosis. Compared with the conventional CHF3 and C4F8 mixed plasma, the C7F14 mixed plasma exhibited a more perpendicular etching profile with higher SiON/Si selectivity and a smoother surface.


2021 ◽  
Vol 21 (10) ◽  
pp. 5157-5164
Author(s):  
Junmyung Lee ◽  
Yeonsik Choi ◽  
Yunho Nam ◽  
Byung Jun Lee ◽  
Hyun Woo Lee ◽  
...  

Silicon oxycarbide (SiOC) film was etched using a CF4/C6F12O/O2 mixed gas plasma through an inductively coupled plasma etcher. Changes in the dielectric constant and surface chemical bonding properties were investigated using ellipsometry and Fourier transform infrared spectroscopy. Plasma diagnosis was carried out using a double Langmuir probe, ultraviolet detector, and residual gas analyzer. The physical and chemical plasma properties of CHF3 and C6F12O exhibited similar trends. However, the C6F12O mixed plasma exhibited a smaller change in dielectric constant compared to that of a conventional CHF3 mixed plasma, because of the lower ion density, ion energy flux, and UV intensity and thinner fluorocarbon-based polymer formation. Therefore, the liquefied C6F12O gas can substitute for the existing etching process gas and reduce the change in dielectric constant.


2019 ◽  
Vol 34 (5) ◽  
pp. 891-898 ◽  
Author(s):  
Guilherme Luiz Scheffler ◽  
Dirce Pozebon ◽  
Diane Beauchemin

Adding nitrogen to the plasma gas in ICPOES significantly improves sensitivity and limit of detection for solid sampling ETV.


1997 ◽  
Vol 473 ◽  
Author(s):  
C. L. Kim ◽  
K. H. Kwon ◽  
S. J. Yu ◽  
H. J. Kim ◽  
E. G. Chang

ABSTRACTThe effect of grain boundary on the corrosion of Al(Cu 1%) etched using SiCl4/Cl2/He/CHF3 gas plasma has been evaluated with XPS (X-ray photoelectron spectroscopy), SEM (scanning electron microscopy) and AES (Auger electron spectroscopy). It was found with SEM that the surface of Al(Cu 1 %) mainly corroded at the grain boundary. Using AES point analysis, the cause of selective corrosion at the grain boundary of Al(Cu 1 %) has been investigated. The results of AES indicated that the contents of F and Cl have made a difference at the analyzed positions. This seems to result from the imperfect crystalline structure of Al(Cu 1%) grain boundary. It was also confirmed that F has passivated the Cl at the grain boundary. The SEM and XPS results implied that Cl incorporated in the grain boundary of polycrystalline Al(Cu 1%) film accelerated the corrosion and could not be easily removed by the subsequent SF6 plasma treatment.


1990 ◽  
Vol 200 ◽  
Author(s):  
S. Matsubara ◽  
T. Sakuma ◽  
S. Yamamichi ◽  
H. Yamaguchi ◽  
Y. Miyasaka

ABSTRACTSrTiO3 thin film preparation onto Si substrates using RF magnetron sputtering has been studied for a high capacitance density required for the next generation of LSI's. Structural and chemical analysis on the interface between SrTiO3 film and Si was carried out with cross-sectional TEM, EDX, and AES. Dielectric properties were measured on AuTi/SrTiO3/Si/Ti/Au capacitors. The as-grown dielectric films on Si were analyzed and found to consist of three layers; SiO2, amorphous SrTiO3 and crystalline SrTiO3, from interface toward film surface. By annealing at 600 °C, the amorphous SrTiO3 layer was recrystallized, and consequently the capacitance value increased. A typical specific capacitance was 4.7 fF/μm2 and the leakage current was in the order of 10−8 A/cm2, for 180 nm thick SrTiO3 film. The dielectric constant decreased from 147 to 56 with decreasing SrTiO3 film thickness from 480 nm to 80 nm. This is due to the low dielectric constant SiO2 layer (ε=3.9) at the interface. From the film thickness dependence of the ε value, the SiO2 layer thickness was calculated to be 3.9 nm, which agreed well with the value directly observed in the TEM.To avoid SiO2 layer formation, barrier layers between SrTiO3 and Si have been studied. Among various refractory and noble metals, RuSi and a multi-layer of Pt/Ti have been found to be promising candidates for the barrier material. When RuSi film or Pt/Ti film was formed between SrTiO3 film and Si substrate, dielectric constant of about 190 was obtained in dependent of the SrTiO3 film thickness in the range of 80–250 nm. Analysis on the barrier layers was performed by means of RBS, XPS and XRD.


Sign in / Sign up

Export Citation Format

Share Document