- Email: [email protected]
Properties of depth-profile controlled boron nitride films prepared by ion-beam assisted deposition
Nuclear Instruments and Methods in Physics ResearchB 127/128 (19971977-980
NUMB mam Intoredon withuateria
EIBVIER Properties
of depth-profile controlled boron nitride films prepared by ion-beam assisted deposition
*,
M. Kumagai a- M. Suzuki a, T. Suzuki b, Y. Tanaka b, Y. Setsuhara b, S. Miyake b, K. Ogata ‘, M. Kohata d, K. Higeta e, T. Einishi f, Y. Suzuki g, Y. Shimoitani h, Y. Motonami i a Kanagawa High-Technology Foundation, Kawasaki. 213 Japan b Joining aad Welding Research Institute. Osaka Uniuersity, Osaka, 567 Japan ’ Nissin Electric Co., Ltd., Kyoto, 615 Japan e Toshiba Tungaloy Co., Ltd., Iwaki, 970-l 1 Japan e Chugai Ro Co., Ltd., Osaka, 592 Japan t Isuzu Glass Co., Ltd.. Osaka, 557 Japan g MINOLTA Co., Ltd., Osaka, 569 Japan h Alloy Industries Ltd., Okayama, 719-31 Japan i Starloy Industries Ltd., Matsubara, 580 Japan
Abstract
Boron nitride films were prepared by vapor deposition of boron and simultaneous bombardment with mixed gas ions of nitrogen and argon in the energy range of 0.2 to 20 keV. The films were prepared on various kinds of substrates including silicon wafers, tungsten carbide plates and various ceramic plates at a temperature of 400°C. In the synthesis of the BN films, a boron-rich buffer layer between the substrate and the BN film was formed by energetic nitrogen ion beam bombardment, improving tribological properties such as the depth-profile controlled layer. The buffer layer improved film adhesion, and chemical stability, thermal stability at elevated temperature and corrosion resistance of the BN films also gave good results.
1. Introduction
Cubic boron nitride (c-BN) has prominent properties similar to diamond such as extreme hardness and high chemical stability and the various potential applications of c-BN films on a tribological use have been studied [l]. However, there have been few reports of the successful results on the properties because of pure adhesion strength between substrates and BN films. It is generally hard to prepare the films with good adhesion, because of the internal stress in the films that is formed during the synthesis of c-BN crystalline structure [2]. In this paper, we report the formation of c-BN films with good adhesion prepared by the ion beam assisted deposition (IBAD) method and some results of triobological properties. The c-BN film was formed by boron evaporation under simultaneous ion beam bombardment of nitrogen and ar-
* Corresponding author. Kanagawa High-Technology Foundation, Kanagawa Science Park, 3-2- 1 Sakado, Takatsu-ku, Kawasaki 213, Japan. Tel.: +(81X44)819-2105, Fax: +(81x44)819-2108, E-mail: [email protected]. 0168-583X/97/$17.00
gon mixture gas on a buffer layer, which was boron-rich between the substrate and c-BN film to improve the adhesion strength. The film structure was evaluated by Fourier transform infrared spectrometry, and the anti-corrosion properties, the chemical stability and the thermal stability at elevated temperature were studied in view of practical uses, based on the improvement of surface toughness for mechanical parts such as cutting tool, glass moulds and so on.
2. Experimental The equipment used for preparation was a dual beam IBAD system. The details of this machine have been described elsewhere [3]. This machine is equipped with two ion sources which are operated in the high energy (2-20 keV1 and low energy (0.2-2 keV1 regions. In the present work, we prepared the BN films using both energy ion sources to form the c-BN films and the buffer layer. The acceleration voltage of the ion beams was varied in the range of 0.2-20 keV to form the c-BN films. In order to enhance the crystalline growth by deposited energy of
0 1997 Elsevier Science B.V. All rights reserved
PII SO168-583X(97)00042-6
VI. APPLICATIONS
978
M. Kumagai et al./ Nucl. Instr. and Meth. in Phys. Rex B 127 / 128 (1997) 977-980
ions, a mixed gas ion beam of nitrogen and argon was irradiated onto the substrate during electron beam bombardment vapor deposition of boron. The ratio of nitrogen and argon ions, N/Ar, was kept at 1.5, and the current density of the ion beam was a constant 0.1 mA/cm*. The (eposition rate of boron was changed from 0.44 to 2.2 A/S to vary the transport ratio of boron and nitrogen atoms over the range 1.0-5.0 (B/N). A buffer layer was prepared with a 10 keV accelerated nitrogen ion beam and the transport ratio, B/N, was kept at 30, because this boron-rich layer improves the adhesion strength through stress relaxation in the films [4]. The thickness of the layer was 1500 A. The substrate temperature was held constant at 400°C by use of a heating system during deposition, and the total thickness of the film including the buffer layer was about 1.0 km. In order to study the relationship between the crystalline growth and the preparation conditions, the BN films formed on the silicon (Si) wafers were evaluated by a Fourier transform infrared spectrometer (IT-IR). Hardness and adhesion strength of the films on both the Si wafers and tungsten carbide (WC) substrates were measured by a Knoop hardness tester with a load of 5 g, and a scratch tester. Anti-corrosion property was evaluated by hydrochloride acid (HCl) liquid drip test on the WC substrate. Thermal stability of the films on the aluminum oxide (Al,O,) ceramics substrates was studied by the change of the Vickers hardness after annealing at 1000°C. In addition, the chemical stability of the films on mirror-polished silicon nitride (Si3N4) ceramic substrates was studied by a glass contact test on the heated film surface. In this test, movement of specific impurities between glass and films was measured by Rutherford back scattering spectroscopy (RBS).
3. Results and discussion In our experiment, the crystalline structure of BN films was controlled by the preparation conditions, such as the substrate temperature, the mixture gas ratio of ions, transport ratio of B/N and ion beam energy [4]. It was shown that the growth of the c-BN crystal phase could be enhanced by low energy ion beam bombardment [4]. FT-IR spectra of the BN films prepared by 1 keV accelerated mixture gas ions on Si substrates without the buffer layer are shown in Fig. 1, where the transport ratio of B/N was varied from 1.0 to 5.0. All of the spectra show the absorption peaks at about 1350 cm-’ and 800 cm-’ from the hexagonal BN [5]. The peak intensity at about 1100 cm-’ that corresponds with the c-BN crystal phase [6] increases and become clearer with increasing transport ratio, except for the spectra from the films with B/N = 4.0 and 5.0. The peak for B/N = 2.0 is highest. In these films with B/N = 2.0, the composition ratio calculated from the ratio of each peak in X-ray photoelectron spectroscopy
Wavenumber
(cm-’ )
Fig. 1. FT-IR spectra of BN films formed on Si substrates by a mixed gas ion beam bombardment of nitrogen and argon gas ions with a ratio of N/Ar = 1.5 during boron vapor deposition. The transport ratio, B/N, to the substratewas changed from 1.0 to 5.0. The temperature of substrates was held constant at 400°C.
and/or Auger electron spectroscopy analysis, correcting for the sensitivity of the detector and photo-ionization cross section, showed a stoichiometric composition of B/N = 1.0. These results show that the crystalline structure depends on the transport ratio of B/N and on ion beam energy. However, the films with only c-BN crystal phase have insufficient adhesion strength. Fig. 2 shows the surface morphology observed by optical microscope for the films prepared by a transport ratio of B/N = 2.0 on the Si substrate. Each film is shown with and without the buffer layer. The film with buffer layer shows a smooth surface, but that without the buffer layer shows many moir6 patterns caused by peeling (Fig. 2(b)), probably resulting from residual internal stresses between the substrate and film. Fig. 3 shows the relationship between the hardness and the adhesion strength of those films. The adhesion strength decreases with increasing film hardness, but those values are increased by effects of the buffer layers and it also shows that those mechanical properties can be controlled by use of this layer. Knoop hardness and adhesion strength of the film with a buffer layer formed on the WC substrates showed 35.3 GPa and 19 N, respectively. The hardness is more than two times that of the WC substrate, which was 16.8 GPa. On the other hand, the adhesion strength is similar to that of the boron-rich film alone, which was 16.5 N. It means that the adhesion strength of c-BN films consisting of a multi-layer is influenced by the
M. Kumagai et al./Nucl.
Insrr. and Meth. in Phys. Res. B 127/128
strength of buffer layer. Therefore, we investigated the other tribological properties using the c-BN film formed with a transport ratio of B/N - 2.0 with this buffer layer. The anti-corrosion property tested by a drip test using 1 N HCl solution was evaluated by observing surface morphology by optical microscope. Fig. 4 shows BN films and WC substrates 1 minute and 10 minutes later after dripping. On the WC substrate, a few pits appeared on the surface at 1 minute. These increased with passing time and the corrosion over the whole surface appeared at 10 minutes later. However, there was no change on the c-BN film surface after the corrosion test and this suggests that the film has good anti-corrosion properties. The thermal stability of the c-BN films on the Al,O, substrates was studied by the change of the Vickers hardness before and after annealing, such as in Fig. 5. The annealing temperature of the films was held at about 1000°C for 30 minutes in the Ar gas and atmosphere. The films on the substrates was not vanished after annealing and the hardness of them was also not changed. Finally, the chemical stability of the heated film surface
(a) with the buffer layer
979
(1997) 977-980
14[.“-‘.-.“““““‘j
0 with buffer Iaver
u
i
0
10
20
30
40
Knoop hardness (GPa) Fig. 3. The relationship between the Knoop hardness and the adhesion strength of the c-BN films with and without the buffer layer.
was investigated by the glass contact test, and the chemical reaction between the films on SisN, substrates and glass containing a lead (Pb) or titanium (Ti) was evaluated. The
(a) WC substrate
(b) without the buffer layer
I I 100/x
Fig. 2. Surface morphology obtained by optical microscopy of c-BN tihns (a) with the buffer layer prepared by the transport ratio of B/N = 30 with 10 keV nitrogen ion beam bombardment and (b) without buffer layer.
(b) c-BN film on WC substrate I
I
4oop Fig. 4. Surface morphology observed by optical microscopy for the WC substrates and c-BN films on WC substrates after 1 N HCI solution drip test.
VI. APPLICATIONS
M. Kumagai et al./Nucl.
980
Instr. and Meth. in Phys. Res. B 127/ I28 (1997) 977-980
4. Conclusion
non-heating
in the Ar oas
atmosohere
Fig. 5. Vickers hardness measurement of the films on the Al,O, substrates before and after annealing at about lC00” for 30 min-
utes.
temperature of film surface during the contact test was kept at the softening temperature of each glass that was 500°Cfor lead glass and 700°C for titanium glass. Melting adhesion between the glass and the films did not occur. Using RBS analysis, the diffusion of Pb and Ti atoms at near the surface of film and glass after this contact test could not be detected, as Fig. 6. It seems that the c-BN films prepared under the present conditions have good thermal and chemical stability at high temperatures. The c-BN film prepared by the IBAD method is a useful practical material. Q.
Acknowledgements
This work was partially supported by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Science, Sports and Culture under contract Ng 07555521.
I
I
o before contact test x after contact test
x Ar (In the c-BN flims)
References
200
9 al ‘S
Boron nitride films were produced on various substrates by mixed gas ion beam bombardment of nitrogen and argon during deposition of vaporized boron (IBAD). FT-lR analysis of the film formed with 1 keV ion beam bombardment and a transport ratio of B/N = 2.0 showed a clear peak for the cubic BN phase together with small peak for the hexagonal BN phase. The c-BN films with a buffer layer between the film and substrate, produced by a transport ratio of B/N = 30 with 10 keV nitrogen ion beam, has both good adhesion strength, about 19 N, and a hardness of H, s 35 GPa. The anti-corrosion and thermal and chemical stability in the high temperature atmosphere of this film showed the good properties, and the c-BN films prepared by IBAD method with this article conditions is a useful coating material in the practical use.
(In the SI 3N4 substrate)
100
1
c-
Pbsdge
I
Y (in the S13E(asubstrate)
0 350
channel Fig. 6. RBS analysis result near the surface of c-BN films and contacted glass after contact test with glass containing Pb or Ti atoms.
[I] S. Watanabe, S. Miyake and M. Murakawa, Surf. Coat. Technol. 49 0991) 406. [2] T.A. Friedmann, P.B. Mirkarimi, D.L. Medlin, K.F. McCarty, E.J. Klaus, D.R. Boehme, H.A. Johnsen, M.J. Mills and D.K. Ottesen, J. Appl. Phys. 76(5) (1994) 3088. [3] K. Ogata, Y. Andoh and E. Kamijo, NucI. Instr. Methods B33 ( 1988) 685. [4] Y. Setsuhara, T. Suzuki, Y. Tanaka, S. Miyake, M. Suzuki, M. Kumagai, K. Ogata, M. Kohata, K. Higeta, T. Einishi, Y. Suzuki, Y. Shimoitani, Y. Motonami, these Proceedings (IBMM ‘96). Nucl. Ins& and Meth. B 127/128 (1997) 851. [5] R. Geick and C.H. Perry, Phys. Rev. 146 (1966) 543. [6] P.J. Gielisse, S.S. Mitra, J.N. Plenell, R.D. Griffis, L.C. Mansur, R. Marshall and E.A. Pascor, Phys. Rev. 155 (1%7) 1039.
NUMB mam Intoredon withuateria
EIBVIER Properties
of depth-profile controlled boron nitride films prepared by ion-beam assisted deposition
*,
M. Kumagai a- M. Suzuki a, T. Suzuki b, Y. Tanaka b, Y. Setsuhara b, S. Miyake b, K. Ogata ‘, M. Kohata d, K. Higeta e, T. Einishi f, Y. Suzuki g, Y. Shimoitani h, Y. Motonami i a Kanagawa High-Technology Foundation, Kawasaki. 213 Japan b Joining aad Welding Research Institute. Osaka Uniuersity, Osaka, 567 Japan ’ Nissin Electric Co., Ltd., Kyoto, 615 Japan e Toshiba Tungaloy Co., Ltd., Iwaki, 970-l 1 Japan e Chugai Ro Co., Ltd., Osaka, 592 Japan t Isuzu Glass Co., Ltd.. Osaka, 557 Japan g MINOLTA Co., Ltd., Osaka, 569 Japan h Alloy Industries Ltd., Okayama, 719-31 Japan i Starloy Industries Ltd., Matsubara, 580 Japan
Abstract
Boron nitride films were prepared by vapor deposition of boron and simultaneous bombardment with mixed gas ions of nitrogen and argon in the energy range of 0.2 to 20 keV. The films were prepared on various kinds of substrates including silicon wafers, tungsten carbide plates and various ceramic plates at a temperature of 400°C. In the synthesis of the BN films, a boron-rich buffer layer between the substrate and the BN film was formed by energetic nitrogen ion beam bombardment, improving tribological properties such as the depth-profile controlled layer. The buffer layer improved film adhesion, and chemical stability, thermal stability at elevated temperature and corrosion resistance of the BN films also gave good results.
1. Introduction
Cubic boron nitride (c-BN) has prominent properties similar to diamond such as extreme hardness and high chemical stability and the various potential applications of c-BN films on a tribological use have been studied [l]. However, there have been few reports of the successful results on the properties because of pure adhesion strength between substrates and BN films. It is generally hard to prepare the films with good adhesion, because of the internal stress in the films that is formed during the synthesis of c-BN crystalline structure [2]. In this paper, we report the formation of c-BN films with good adhesion prepared by the ion beam assisted deposition (IBAD) method and some results of triobological properties. The c-BN film was formed by boron evaporation under simultaneous ion beam bombardment of nitrogen and ar-
* Corresponding author. Kanagawa High-Technology Foundation, Kanagawa Science Park, 3-2- 1 Sakado, Takatsu-ku, Kawasaki 213, Japan. Tel.: +(81X44)819-2105, Fax: +(81x44)819-2108, E-mail: [email protected]. 0168-583X/97/$17.00
gon mixture gas on a buffer layer, which was boron-rich between the substrate and c-BN film to improve the adhesion strength. The film structure was evaluated by Fourier transform infrared spectrometry, and the anti-corrosion properties, the chemical stability and the thermal stability at elevated temperature were studied in view of practical uses, based on the improvement of surface toughness for mechanical parts such as cutting tool, glass moulds and so on.
2. Experimental The equipment used for preparation was a dual beam IBAD system. The details of this machine have been described elsewhere [3]. This machine is equipped with two ion sources which are operated in the high energy (2-20 keV1 and low energy (0.2-2 keV1 regions. In the present work, we prepared the BN films using both energy ion sources to form the c-BN films and the buffer layer. The acceleration voltage of the ion beams was varied in the range of 0.2-20 keV to form the c-BN films. In order to enhance the crystalline growth by deposited energy of
0 1997 Elsevier Science B.V. All rights reserved
PII SO168-583X(97)00042-6
VI. APPLICATIONS
978
M. Kumagai et al./ Nucl. Instr. and Meth. in Phys. Rex B 127 / 128 (1997) 977-980
ions, a mixed gas ion beam of nitrogen and argon was irradiated onto the substrate during electron beam bombardment vapor deposition of boron. The ratio of nitrogen and argon ions, N/Ar, was kept at 1.5, and the current density of the ion beam was a constant 0.1 mA/cm*. The (eposition rate of boron was changed from 0.44 to 2.2 A/S to vary the transport ratio of boron and nitrogen atoms over the range 1.0-5.0 (B/N). A buffer layer was prepared with a 10 keV accelerated nitrogen ion beam and the transport ratio, B/N, was kept at 30, because this boron-rich layer improves the adhesion strength through stress relaxation in the films [4]. The thickness of the layer was 1500 A. The substrate temperature was held constant at 400°C by use of a heating system during deposition, and the total thickness of the film including the buffer layer was about 1.0 km. In order to study the relationship between the crystalline growth and the preparation conditions, the BN films formed on the silicon (Si) wafers were evaluated by a Fourier transform infrared spectrometer (IT-IR). Hardness and adhesion strength of the films on both the Si wafers and tungsten carbide (WC) substrates were measured by a Knoop hardness tester with a load of 5 g, and a scratch tester. Anti-corrosion property was evaluated by hydrochloride acid (HCl) liquid drip test on the WC substrate. Thermal stability of the films on the aluminum oxide (Al,O,) ceramics substrates was studied by the change of the Vickers hardness after annealing at 1000°C. In addition, the chemical stability of the films on mirror-polished silicon nitride (Si3N4) ceramic substrates was studied by a glass contact test on the heated film surface. In this test, movement of specific impurities between glass and films was measured by Rutherford back scattering spectroscopy (RBS).
3. Results and discussion In our experiment, the crystalline structure of BN films was controlled by the preparation conditions, such as the substrate temperature, the mixture gas ratio of ions, transport ratio of B/N and ion beam energy [4]. It was shown that the growth of the c-BN crystal phase could be enhanced by low energy ion beam bombardment [4]. FT-IR spectra of the BN films prepared by 1 keV accelerated mixture gas ions on Si substrates without the buffer layer are shown in Fig. 1, where the transport ratio of B/N was varied from 1.0 to 5.0. All of the spectra show the absorption peaks at about 1350 cm-’ and 800 cm-’ from the hexagonal BN [5]. The peak intensity at about 1100 cm-’ that corresponds with the c-BN crystal phase [6] increases and become clearer with increasing transport ratio, except for the spectra from the films with B/N = 4.0 and 5.0. The peak for B/N = 2.0 is highest. In these films with B/N = 2.0, the composition ratio calculated from the ratio of each peak in X-ray photoelectron spectroscopy
Wavenumber
(cm-’ )
Fig. 1. FT-IR spectra of BN films formed on Si substrates by a mixed gas ion beam bombardment of nitrogen and argon gas ions with a ratio of N/Ar = 1.5 during boron vapor deposition. The transport ratio, B/N, to the substratewas changed from 1.0 to 5.0. The temperature of substrates was held constant at 400°C.
and/or Auger electron spectroscopy analysis, correcting for the sensitivity of the detector and photo-ionization cross section, showed a stoichiometric composition of B/N = 1.0. These results show that the crystalline structure depends on the transport ratio of B/N and on ion beam energy. However, the films with only c-BN crystal phase have insufficient adhesion strength. Fig. 2 shows the surface morphology observed by optical microscope for the films prepared by a transport ratio of B/N = 2.0 on the Si substrate. Each film is shown with and without the buffer layer. The film with buffer layer shows a smooth surface, but that without the buffer layer shows many moir6 patterns caused by peeling (Fig. 2(b)), probably resulting from residual internal stresses between the substrate and film. Fig. 3 shows the relationship between the hardness and the adhesion strength of those films. The adhesion strength decreases with increasing film hardness, but those values are increased by effects of the buffer layers and it also shows that those mechanical properties can be controlled by use of this layer. Knoop hardness and adhesion strength of the film with a buffer layer formed on the WC substrates showed 35.3 GPa and 19 N, respectively. The hardness is more than two times that of the WC substrate, which was 16.8 GPa. On the other hand, the adhesion strength is similar to that of the boron-rich film alone, which was 16.5 N. It means that the adhesion strength of c-BN films consisting of a multi-layer is influenced by the
M. Kumagai et al./Nucl.
Insrr. and Meth. in Phys. Res. B 127/128
strength of buffer layer. Therefore, we investigated the other tribological properties using the c-BN film formed with a transport ratio of B/N - 2.0 with this buffer layer. The anti-corrosion property tested by a drip test using 1 N HCl solution was evaluated by observing surface morphology by optical microscope. Fig. 4 shows BN films and WC substrates 1 minute and 10 minutes later after dripping. On the WC substrate, a few pits appeared on the surface at 1 minute. These increased with passing time and the corrosion over the whole surface appeared at 10 minutes later. However, there was no change on the c-BN film surface after the corrosion test and this suggests that the film has good anti-corrosion properties. The thermal stability of the c-BN films on the Al,O, substrates was studied by the change of the Vickers hardness before and after annealing, such as in Fig. 5. The annealing temperature of the films was held at about 1000°C for 30 minutes in the Ar gas and atmosphere. The films on the substrates was not vanished after annealing and the hardness of them was also not changed. Finally, the chemical stability of the heated film surface
(a) with the buffer layer
979
(1997) 977-980
14[.“-‘.-.“““““‘j
0 with buffer Iaver
u
i
0
10
20
30
40
Knoop hardness (GPa) Fig. 3. The relationship between the Knoop hardness and the adhesion strength of the c-BN films with and without the buffer layer.
was investigated by the glass contact test, and the chemical reaction between the films on SisN, substrates and glass containing a lead (Pb) or titanium (Ti) was evaluated. The
(a) WC substrate
(b) without the buffer layer
I I 100/x
Fig. 2. Surface morphology obtained by optical microscopy of c-BN tihns (a) with the buffer layer prepared by the transport ratio of B/N = 30 with 10 keV nitrogen ion beam bombardment and (b) without buffer layer.
(b) c-BN film on WC substrate I
I
4oop Fig. 4. Surface morphology observed by optical microscopy for the WC substrates and c-BN films on WC substrates after 1 N HCI solution drip test.
VI. APPLICATIONS
M. Kumagai et al./Nucl.
980
Instr. and Meth. in Phys. Res. B 127/ I28 (1997) 977-980
4. Conclusion
non-heating
in the Ar oas
atmosohere
Fig. 5. Vickers hardness measurement of the films on the Al,O, substrates before and after annealing at about lC00” for 30 min-
utes.
temperature of film surface during the contact test was kept at the softening temperature of each glass that was 500°Cfor lead glass and 700°C for titanium glass. Melting adhesion between the glass and the films did not occur. Using RBS analysis, the diffusion of Pb and Ti atoms at near the surface of film and glass after this contact test could not be detected, as Fig. 6. It seems that the c-BN films prepared under the present conditions have good thermal and chemical stability at high temperatures. The c-BN film prepared by the IBAD method is a useful practical material. Q.
Acknowledgements
This work was partially supported by a Grant-in-Aid for Scientific Research from the Japanese Ministry of Education, Science, Sports and Culture under contract Ng 07555521.
I
I
o before contact test x after contact test
x Ar (In the c-BN flims)
References
200
9 al ‘S
Boron nitride films were produced on various substrates by mixed gas ion beam bombardment of nitrogen and argon during deposition of vaporized boron (IBAD). FT-lR analysis of the film formed with 1 keV ion beam bombardment and a transport ratio of B/N = 2.0 showed a clear peak for the cubic BN phase together with small peak for the hexagonal BN phase. The c-BN films with a buffer layer between the film and substrate, produced by a transport ratio of B/N = 30 with 10 keV nitrogen ion beam, has both good adhesion strength, about 19 N, and a hardness of H, s 35 GPa. The anti-corrosion and thermal and chemical stability in the high temperature atmosphere of this film showed the good properties, and the c-BN films prepared by IBAD method with this article conditions is a useful coating material in the practical use.
(In the SI 3N4 substrate)
100
1
c-
Pbsdge
I
Y (in the S13E(asubstrate)
0 350
channel Fig. 6. RBS analysis result near the surface of c-BN films and contacted glass after contact test with glass containing Pb or Ti atoms.
[I] S. Watanabe, S. Miyake and M. Murakawa, Surf. Coat. Technol. 49 0991) 406. [2] T.A. Friedmann, P.B. Mirkarimi, D.L. Medlin, K.F. McCarty, E.J. Klaus, D.R. Boehme, H.A. Johnsen, M.J. Mills and D.K. Ottesen, J. Appl. Phys. 76(5) (1994) 3088. [3] K. Ogata, Y. Andoh and E. Kamijo, NucI. Instr. Methods B33 ( 1988) 685. [4] Y. Setsuhara, T. Suzuki, Y. Tanaka, S. Miyake, M. Suzuki, M. Kumagai, K. Ogata, M. Kohata, K. Higeta, T. Einishi, Y. Suzuki, Y. Shimoitani, Y. Motonami, these Proceedings (IBMM ‘96). Nucl. Ins& and Meth. B 127/128 (1997) 851. [5] R. Geick and C.H. Perry, Phys. Rev. 146 (1966) 543. [6] P.J. Gielisse, S.S. Mitra, J.N. Plenell, R.D. Griffis, L.C. Mansur, R. Marshall and E.A. Pascor, Phys. Rev. 155 (1%7) 1039.