금속 Ni 분말을 용해하여 제조된 용액에서 Ni 농도 변화가 전기도금 된 Ni 필름 특성에 미치는 영향

윤필근,박덕용,Yoon, Pilgeun,Park, Deok-Yong 한국표면공학회 2019 한국표면공학회지 Vol.52 No.2

Chloride baths for electrodeposited Ni thin films were fabricated by dissolving metal Ni powders with the mixed solution consisting of HCl and de-ionized water. Current efficiency, residual stress, surface morphology and microstructure of Ni films with the change of metal ion ($Ni^{2+}$) concentrations in the plating solution were studied. Current efficiency was measured to be more than 90% with increasing $Ni^{2+}$ concentrations in the plating solution. Residual stress of Ni thin film was increased from about 400 to 780 MPa with increasing $Ni^{2+}$ concentration from 0.2 to 0.5 M. It is gradually decreased to 650 MPa at 0.9 M $Ni^{2+}$ concentration. Smooth surface morphologies were observed over 0.3 M $Ni^{2+}$ concentration, but nodule surface morphology at 0.2 M. Ni films consist of FCC(111), FCC(200), FCC(220) and FCC(311) peaks in XRD patterns. Preferred orientation of FCC(111) was observed and its intensity was slightly decreased with increasing $Ni^{2+}$ concentration. The average grain size was slightly increased at 0.3 M $Ni^{2+}$ concentration and then slightly decreased with increasing $Ni^{2+}$ concentration.

금속 Ni 분말을 용해한 도금용액으로부터 전기도금 된 Ni 박막 특성에 미치는 도금조건의 영향

윤필근(Pilgeun Yoon),박근용(Keun-Yong Park),엄영랑(Young Rang Uhm),최선주(Sun Ju Choi),박덕용(Deok-Yong Park) 한국표면공학회 2015 한국표면공학회지 Vol.48 No.3

Chloride plating solution was fabricated by dissolving metal Ni powders in solution with HCl and deionized water. Effects of deposition conditions on the properties of Ni films electrodeposited from chloride baths were studied. Current efficiency of Ni films electrodeposited from the baths containing saccharin was decreased with increasing the current density. Residual stress of Ni thin films ware measured to be about 230 ~ 435 MPa in the range of current density of 10 ~ 25 mA/cm<SUP>2</SUP>. Cathode current efficiency in baths without saccharin was initially increased with increasing pH, while it was decreased with increasing pH further. Cathode current efficiency in baths with saccharin (except at pH 2) exhibited less 10 ~ 20% than that in baths without saccharin. Residual stress of Ni films electrodeposited from baths without saccharin was measured to be 388 ~ 473 MPa in the range of pH 2 ~ pH 5 and then was increased to 551 MPa at pH 6. On the other hand, residual stress of Ni films electrodeposited from baths with saccharin was increased with increasing pH. Surface morphology was strongly affected by the change of current density, but slightly by solution pH and addition of saccharin.

63Ni 밀봉선원용 Ni 전기도금 박막에서 Ni 농도가 잔류응력에 미치는 영향

윤필근(Pilgeun Yoon),박덕용(Deok-Yong Park) 한국표면공학회 2017 한국표면공학회지 Vol.50 No.1

Chloride plating solution was fabricated by dissolving metal Ni powders in a mixed solution with HCl and de-ionized water. Effects of Ni2+ and saccharin concentrations in the plating baths on current efficiency, residual stress, surface morphology and microstructure of Ni films were studied. In the case of 0.2 M Ni2+ concentration, current efficiency was decreased to about 65 % with increasing saccharin concentration, but, in the case of 0.7 M Ni2+ concentration, it was shown more than 90 % with the increase of saccharin concentration. Residual stress of Ni thin film was appeared to be about 400 MPa up to 0.0244 M saccharin concentration at the 0.2 M Ni2+ concentration and surface morphology with severe cracks was observed in the range of 0.0487~0.0975 M saccharin concentration. Residual stress of Ni thin films was measured to be about 750 MPa without saccharin addition and 114~148 MPa at the range of 0.0097~0.0975 M saccharin concentration for the 0.7 M Ni2+ concentration. Relatively low residual stress values (114~148 MPa) of the Ni films at the range of 0.0097~0.0975 M saccharin concentration may be resulted from codeposition of S from saccharin. Ni films at 0.7 M Ni2+ concentration showed smooth surface morphology and were independent of saccharin concentration. Ni films at 0.7 M Ni2+ concentration consist of FCC(111), FCC(200), FCC(220) and FCC(311) peaks and the intensities of FCC(111) and FCC(200) peaks increased with increasing saccharin concentration. Also, the average grain size decreased with increasing saccharin concentration from about 30 nm to about 15 nm.

피로인산동 도금용액으로부터 전기도금 된 Cu 도금층의 물성에 미치는 인가전류밀도의 영향

윤필근(Pilgeun Yoon),박덕용(Deok-Yong Park) 한국표면공학회 2020 한국표면공학회지 Vol.53 No.4

Copper pyrophosphate baths were employed in order to study the dependencies of current efficiency, residual stress, surface morphology and microstructure of electrodeposited Cu thin layers on applied current density. The current efficiency was obtained to be more than about 90 %, independent of the applied current density. Residual stress of Cu electrodeposits was measured to be in the range of -30 ㎫ and 25 ㎫ with the increase of applied current density from 0.5 to 15 ㎃/㎠. Relatively smooth surface morphologies of the electodeposited Cu layers were obtained at an intermediate current range between 3 and 4 ㎃/㎠. The Cu electrodeposits showed FCC(111), FCC(200), and FCC(220) peaks and any preferred orientation was not observed in this study. The average crystalline size of Cu thin layers was measured to be in the range of 44∼69 ㎚.

Ni Sulfamate-chloride 전기도금 용액에서 전류밀도와 첨가제의 농도 변화가 Ni 박막에 미치는 영향

윤필근(Pilgeun Yoon),박덕용(Deok-Yong Park) 한국표면공학회 2018 한국표면공학회지 Vol.51 No.1

Sulfamate plating solution containing a small amount of chloride bath was fabricated to study the properties of the electrodeposited Ni thin films. Effects of the changes of current density and additive concentration on current efficiency, residual stress, surface morphology and microstructure of Ni thin films electrodeposited from Ni sulfamate-chloride baths were investigated. The current efficiency was measured to be more than about 95%, independent of the changes of current density and saccharin concentration in the baths. Residual stress of Ni thin film was appeared to be the compressive stress modes in the range of 5~30 mA/㎠ current density. Maximum compressive stress was observed at the current density of 10 mA/㎠. Compressive stress values of Ni thin/thick films were increased to be about -85~-100 MPa with increasing saccharin concentration from 0 to 0.0195 M(4 g/L). Surface morphology was changed from smooth to nodule surface appearance with increasing the current density. Smooth surface morphology of Ni thin films electrodeposited from the baths containing saccharin was observed, independent of the saccharin concentration. Ni thin/thick films consist of FCC(111), FCC(200), FCC(220), FCC(311) and FCC(222) peaks. It was revealed that the FCC(200) peak of Ni thin films is the preferred orientation in the range of 5~30 mA/㎠ current density. The intensity of FCC(200) peak was gradually decreased and the intensity of FCC(111) peak was increased with increasing saccharin concentration in the baths.

Sulfamate-Chloride Bath에서 Co 농도의 변화에 따른 Ni-Co 필름의 특성 변화

윤필근(Pilgeun Yoon),박덕용(Deok-Yong Park) 한국표면공학회 2020 한국표면공학회지 Vol.53 No.1

Sulfamate-chloride baths were fabricated to study the properties of the electrodeposited Ni and NiCo thin films. The dependences of current efficiency, deposit composition of Ni and Co, residual stress, surface morphology and microstructure of electrodeposited Ni and NiCo thin films on CoCl₂ concentration in sulfamatechloride baths were investigated. The current efficiency was measured to be more than about 90%, independent of the changes of CoCl₂ concentration in the baths. Residual stress of Ni and NiCo thin films was increased from about 45 to about 250 ㎫ with varying CoCl₂ concentration from 0 to 0.210 M CoCl₂ in the baths and then reached to a plateau, about 250 ㎫ above 0.420 M CoCl₂ concentration. Nodular surface morphologies were observed at most CoCl₂ concentrations in the baths except 0.210 M. NiCo thin film electrodeposited from the bath with 0.210 M CoCl₂ concentration showed an acicular surface morphology. Pure Ni thin film consists of FCC(111), FCC(200), FCC(220), and FCC(311) peaks without any preferred orientation. On the other hand NiCo thin films make up of HCP(100), FCC(111), HCP(101), FCC(200), FCC(220) or HCP(110), FCC(311) or HCP(112) and FCC(222) peaks. It was revealed from the analysis of XRD result that FCC(111) peak at the NiCo thin film electrodeposited from the bath with 0.084 M CoCl₂ concentration can be regarded as the preferred orientation. However the peak of the preferred orientation was changed to FCC(220) or HCP(110) above 0.084 M CoCl₂ concentration in the baths. Then the intensity of FCC(220) or HCP(110) peak was gradually decreased with increasing CoCl₂ concentration further. The crystalline size of pure Ni thin film was observed to be about 53 ㎛ and those of NiCo thin films were in the range of 35~45 ㎛.