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The influence on the plasma and the coating caused through a combination of steered arc and modified pulsed arc processes
Surface & Coatings Technology 200 (2005) 634 – 638 www.elsevier.com/locate/surfcoat
The influence on the plasma and the coating caused through a combination of steered arc and modified pulsed arc processes E. HettkampT, H. Mecke Otto-von-Guericke-University of Magdeburg, Institute of Electric Power Systems, Universitaetsplatz 2, 39106 Magdeburg, Germany Available online 10 March 2005
Abstract A combination of steered arc process and modified pulsed arc process was investigated in order to determine the effects on the plasma and on the coating qualities during deposition. Titanium, titanium–aluminium and chromium were used as target materials. The work pressure was 1 Pa with nitrogen as work gas. The usage of a pulsed arc current instead of a continuous arc current leads to an accelerated spot movement during the pulse period. The pulse phase also causes the division of the formerly single spot into multiple spots. Those multiple spots move on average on the circular trace that can be observed also without pulsed arc currents. Therefore the spot traces and their velocity leave vary only locally while the pulse current is applied. Another trait of the process combination is the attenuation of the plasma focussing compared with the pure modified pulsed arc process. This weakening influences the film thickness uniformity. D 2005 Elsevier B.V. All rights reserved. Keywords: Vacuum arc; Pulsed arc; Steered arc; Magnetic field
1. Introduction These investigations are based on the cathodic arc deposition which can be divided into different process variants [1]. Starting from investigations to the random arc, steered arc and modified pulsed arc procedures, the behaviour of the arc discharge was considered with simultaneous action of arc current pulses and magnetic fields. For this purpose the magnetic field is generated by permanent magnets located below the target. The subjects of the experiments were the effects of the process combination on the spot movement, the ion current, and the droplet emission. The d.c. steered arc process finds a broad industrial application. Depending on the magnetic field strength weakly controlled and strongly controlled arcs can be distinguished [2,3]. Also a modification of the spatial emission characterT Corresponding author. Tel.: +49 391 6711073; fax: +49 391 6712408. E-mail address: [email protected] (E. Hettkamp). 0257-8972/$ - see front matter D 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.surfcoat.2005.02.043
istics in arrangement to the random arc was observed if magnetic fields were applied [4]. The changed spot movement behaviour leads to a decrease of the droplet emission but also to a decrease of the attainable deposition rates [5,6]. The modified pulsed arc process offers the possibility to change individual electric parameters directly (for example edge steepness, pulse frequency and pulse duration) [2]. This has effects on the properties of plasma and deposition [7].
2. Experimental details The examinations were carried out in a vacuum coating system bHTC 625 Multi-Lab ABSQ (Hauzer Techno Coating). Evaporators from the company bEifeler WerkzeugeQ were installed into this plant. Titanium, titanium–aluminium and chromium were used as target materials. The working pressure of the nitrogen was 1 Pa. The substrate material was stainless steel. The investigation of the spot movement was realised through a high speed camera. The focus here was on
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
635
probe 0º probe 22,5º
probe 45º
140.0
50.0
target
calculated "d.c.-trace"
26.0
permanent magnet
9.5 10.5
Fig. 1. Arrangement of the ion current probes.
the kind of the movement and rates of the spots that occur. The measurement of the ion current took place with the aid of three probes which were arranged spatially to the target. One of the probes was perpendicularly above the middle of the target. The two other probes were arranged in an angle of 22.58 and 458 to the vertical (Fig. 1). For the evaluation of the layer qualities photos with a 500 times enlargement were taken from the substrate surface. These photos were evaluated with the software banalySISQ and the droplets were analysed according to their size and their face part.
The deposition rates and the layer thickness distributions were determined by the determination of the layer thicknesses.
3. Results 3.1. Spot movement The utilisation of the process combination of steered arc and modified pulsed arc process caused an acceleration of the spot movement. The movement occurred circularly around the permanent magnet. The diversion of the spots
Fig. 2. Comparison of spot movement during modified pulsed arc process and combination with steered arc process (I G = 80 A, I P = 400 A, f P = 00 Hz, and t P = 0.7 ms).
636
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
0,8
Table 1 Samples for average speed of spot movement
Random arc process
Steered arc process
Modified pulsed arc process Process combination
– – – – – – – – 200 200 200 200 200 200 200 200
t pulse [s]
80 100 120 140 80 100 120 140 0.5 0.6 0.7 0.8 0.5 0.6 0.7 0.8
I base [A]
– – – – – – – – 80 80 80 80 80 80 80 80
I pulse [A]
– – – – – – – – 400 400 400 400 400 400 400 400
Average speed of spots (titanium) [m/s] 7.6 8.7 7.7 9.7 17.9 19.5 22.0 22.5 10.3 11.1 17.6 15.5 19.6 19.2 22.5 24.2
Average speed of spots (chrome) [m/s] 4.1 5.2 7.2 8.0 11.3 14.8 16.3 12.2 9.4 12.2 11.8 10.6 16.0 13.1 13.5 15.2
probe 0°
0,4 0,0 20
0,8
iion in A
f pulse [Hz]
40
60
80
100
probe 22,5° 0,4 0,0 0,8 0
20
40
60
80
100
probe 45° 0,4 0,0 0
20
40
60
80
100
t in ms Fig. 3. Shape of ion current for combination of steered arc and modified pulsed arc process (Ti: I G = 80 A, I P = 400 A, t P = 0.6 ms, f P = 200 Hz, V BIAS = V probe = 100 V, and p = 1 Pa).
during the current pulse was superimposed by the circular d.c. trace. It resulted in modifications concerning the trace and the speed of the individual spots. A fan-shaped movement of spots into the direction of the motion of the circular d.c. trace was observed at titanium and chrome as target materials (Fig. 2). Since the spot moved predominantly towards the direction of this circular orbit, the area on which an abrasion occurs was reduced. Measured speeds of spot movement can be taken from Table 1.
observed. This is a reference for a change of the spatial emission characteristics of the modified pulsed arc process through the process combination (Table 2). The focussing of the plasma as it is known for the modified pulsed arc process is weakened by the permanent magnetic field. The observation of the ion current values, cf. Fig. 3, reveals a considerable difference during the pulse phases for the 458 probe. This is caused by the rotation of the spots along the target. Therefore, the change in distance between the current probes and the arc spots results directly in a pulsation of the measured current values.
3.2. Ion current measurements with single probes
3.3. Layer qualities
The average ion current was reduced for probe 08 and 22.58 for the process combination in arrangement with a steered arc process. At the probe 458 an increase of the average ion current (up to 17% for a TiAl target) was
In Fig. 4 shapes of the layer thickness on a 22 cm substrate are represented. The film thickness uniformity for the process combination resembles to the uniformity for the steered arc process. The focussing of the plasma, which is
Table 2 Comparison of average ion current related to arc current (I arc, average = 120 A, I G = 80 A, I P = 400 A, t P = 0.7 ms, f P = 200 Hz, V BIAS = V probe = 100 V, p = 1 Pa, and distance target–probe: 140 mm) I ionMW / I arcMW [mA/A] Random arc
Steered arc
Modified PA
Combination
Modified pulsed arc process related to random arc [%]
Steered arc related to random arc [%]
Combination related to steered arc [%]
TiN Probe 08 Probe 22.58 Probe 458
0.281 0.172 0.153
0.188 0.146 0.154
0.411 0.256 0.163
0.187 0.148 0.171
51.7 49.5 6.6
30.7 15.1 0.6
0.6 1.8 11.2
TiAlN Probe 08 Probe 22.58 Probe 458
0.237 0.145 0.135
0.149 0.138 0.123
0.326 0.179 0.132
0.138 0.136 0.144
37.6 23.6 2.8
37.1 4.9 9.1
7.6 1.3 17.4
CrN Probe 08 Probe 22.58 Probe 458
0.401 0.328 0.184
0.191 0.182 0.141
0.693 0.527 0.215
0.172 0.174 0.143
72.8 60.7 16.7
52.5 44.4 23.3
9.9 4.7 1.0
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
thin film thickness in µm
9
steered arc lower droplet ratios depending on the chosen pulse parameters were determined.
random arc steered arc (1) modified pulsed arc process (2) combination of processes (1+2)
8 7
637
6
4. Discussion
5 4 3 2 1 -10 -8
-6
-4
-2
0
2
4
6
8
10
position on the substrate in cm Fig. 4. Film thickness uniformity for CrN for various used coating technologies with equal average arc current and coating time (TiN: I arc, avg J 120 A, V BIAS = 200 V, and p = 1 Pa).
typical for the modified pulsed arc process, is lost through the effect of the magnetic field. A measurement of the film thicknesses showed an increase of the deposition rate for CrN by approx. 18% for the process combination in the arrangement to the steered arc. The evaluation of the droplets showed that in case of application of the process combination, as also during the pure steered arc process, there are no droplets larger than 10 Am (Table 3). The area part of the droplets on the entire surface was most of the time less than half during the steered arc process in comparison with the random arc. A comparison of the process combination with the modified pulsed arc process showed also a decrease of the area part of the droplets. According to the chosen pulse parameters of the arc current the droplet ratio was decreased between 8% and 75% through application of the process combination for the chosen example with chrome as a target material. Even with a comparison of the process combination with the
The directed movement of the spots influences the plasma qualities. The average ion current, which was measured with the stationary probes, was influenced by the choice of the used process. The average ion current at the probes by 08 and 22.58 was reduced for a comparison of the process combination with a steered arc process. At the probe 458 an increase of the average ion current is observed through the order of the probe and the circular movement of the spots. The resulting layer thickness uniformity for the process combination resembles qualitatively to the process for the layer thickness uniformity from the steered arc. The evaluation of the droplets showed that in case of the process combination, as also during the pure steered arc process, there are no droplets larger than 10 Am. According to the chosen pulse parameters the droplet ratio was reduced through the process combination.
5. Conclusions An accelerated movement of the spots is caused by a combination of steered arc and modified pulsed arc process. The spots move around the circular d.c. trace which is forced by the permanent magnet deflected to both sides (fan-shaped movement) during the current pulses. Through an increase of the speed of the spots and consequently the avoidance of local overheating the process combination in comparison with the modified pulsed arc process results in droplet reduction.
Table 3 Comparison of droplet distribution for the modified pulsed arc process and the combination of steered arc and modified pulsed arc process (CrN: V BIAS = 200 V, p = 1 Pa, and t coat = 20 min)
Modified pulsed arc
Combination
f p (Hz)
t p (s)
I G (A)
I p (A)
200 200 200 200 80 80 80 80 200 200 200 200 80 80 80 80
0.5 0.6 0.7 0.8 0.8 0.8 0.8 0.8 0.5 0.6 0.7 0.8 0.8 0.8 0.8 0.8
80 80 80 80 80 80 80 80 80 80 80 80 80 80 80 80
400 400 400 400 400 500 600 700 400 400 400 400 400 500 600 700
Percentage of area
Total
0.5–1 Am
1.01–2 Am
2.01–5 Am
5.01–10 Am
10.01–20 Am
20.01–30 Am
0.40 0.39 0.43 0.50 0.42 0.41 0.43 0.43 0.60 0.54 0.66 0.34 0.33 0.26 0.51 0.65
2.82 2.37 3.26 3.66 2.91 3.10 2.76 2.88 3.52 3.13 3.79 1.89 1.71 1.42 2.64 3.47
4.51 2.55 4.77 6.32 3.68 4.10 3.89 3.32 2.48 2.24 2.44 1.27 1.12 0.92 1.59 2.21
1.48 1.15 1.80 2.32 1.19 1.42 1.56 0.99 0.36 0.24 0.30 0.17 0.25 0.22 0.41 0.36
1.39 0.18 0.48 0.94 0.90 0.19 0.51 0.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.22 0.00 0.70 0.56 0.00 0.00 0.00 0.37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
10.82 6.64 11.43 14.29 9.10 9.22 9.15 8.27 6.96 6.15 7.19 3.66 3.41 2.81 5.15 6.69
638
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
The combination with the steered arc leads to a modification of the spatial emission characteristic for the modified pulsed arc process. The strong plasma focussing is weakened by the effect of the magnetic field. It could be observed that a process combination of steered arc with the modified pulsed arc process leads to a modification of the layer thickness uniformity with respect to the consideration of single processes.
Acknowledgements This work has been supported by the German Research Foundation.
References [1] P.J. Martin, Cathodic arc deposition, Handbook of Thin Film Process Technology, A1.4, The Institute of Physics, 1995, p. 1. [2] M. Ellrodt, Doctoral thesis, Otto-von-Guericke-University of Magdeburg, 1997. [3] B. Schultrich, P. Siemroth, J. Vetter, O. Zimmer, Vak. Forsch. Prax. 1 (1998) S.37. [4] E. Ertqrk, H.-J. Heuvel, H.-G. Dederichs, Ind.-Anz. 21 (1989) S.22. [5] H.-D. Steffens, L. Cronj7ger, R. Kopp, DqnnschichtechnologienVortr7ge zum Statusseminar, 1990, p. S.465. [6] G.E. Kim, J.-L. Meunier, F. Ajersch, IEEE Trans. Plasma Sci. 23 (6) (1995) S.1001. [7] K. Keutel, E. Hettkamp, H. Fuchs, Thin Solid Films 458 (2004) S.173.
The influence on the plasma and the coating caused through a combination of steered arc and modified pulsed arc processes E. HettkampT, H. Mecke Otto-von-Guericke-University of Magdeburg, Institute of Electric Power Systems, Universitaetsplatz 2, 39106 Magdeburg, Germany Available online 10 March 2005
Abstract A combination of steered arc process and modified pulsed arc process was investigated in order to determine the effects on the plasma and on the coating qualities during deposition. Titanium, titanium–aluminium and chromium were used as target materials. The work pressure was 1 Pa with nitrogen as work gas. The usage of a pulsed arc current instead of a continuous arc current leads to an accelerated spot movement during the pulse period. The pulse phase also causes the division of the formerly single spot into multiple spots. Those multiple spots move on average on the circular trace that can be observed also without pulsed arc currents. Therefore the spot traces and their velocity leave vary only locally while the pulse current is applied. Another trait of the process combination is the attenuation of the plasma focussing compared with the pure modified pulsed arc process. This weakening influences the film thickness uniformity. D 2005 Elsevier B.V. All rights reserved. Keywords: Vacuum arc; Pulsed arc; Steered arc; Magnetic field
1. Introduction These investigations are based on the cathodic arc deposition which can be divided into different process variants [1]. Starting from investigations to the random arc, steered arc and modified pulsed arc procedures, the behaviour of the arc discharge was considered with simultaneous action of arc current pulses and magnetic fields. For this purpose the magnetic field is generated by permanent magnets located below the target. The subjects of the experiments were the effects of the process combination on the spot movement, the ion current, and the droplet emission. The d.c. steered arc process finds a broad industrial application. Depending on the magnetic field strength weakly controlled and strongly controlled arcs can be distinguished [2,3]. Also a modification of the spatial emission characterT Corresponding author. Tel.: +49 391 6711073; fax: +49 391 6712408. E-mail address: [email protected] (E. Hettkamp). 0257-8972/$ - see front matter D 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.surfcoat.2005.02.043
istics in arrangement to the random arc was observed if magnetic fields were applied [4]. The changed spot movement behaviour leads to a decrease of the droplet emission but also to a decrease of the attainable deposition rates [5,6]. The modified pulsed arc process offers the possibility to change individual electric parameters directly (for example edge steepness, pulse frequency and pulse duration) [2]. This has effects on the properties of plasma and deposition [7].
2. Experimental details The examinations were carried out in a vacuum coating system bHTC 625 Multi-Lab ABSQ (Hauzer Techno Coating). Evaporators from the company bEifeler WerkzeugeQ were installed into this plant. Titanium, titanium–aluminium and chromium were used as target materials. The working pressure of the nitrogen was 1 Pa. The substrate material was stainless steel. The investigation of the spot movement was realised through a high speed camera. The focus here was on
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
635
probe 0º probe 22,5º
probe 45º
140.0
50.0
target
calculated "d.c.-trace"
26.0
permanent magnet
9.5 10.5
Fig. 1. Arrangement of the ion current probes.
the kind of the movement and rates of the spots that occur. The measurement of the ion current took place with the aid of three probes which were arranged spatially to the target. One of the probes was perpendicularly above the middle of the target. The two other probes were arranged in an angle of 22.58 and 458 to the vertical (Fig. 1). For the evaluation of the layer qualities photos with a 500 times enlargement were taken from the substrate surface. These photos were evaluated with the software banalySISQ and the droplets were analysed according to their size and their face part.
The deposition rates and the layer thickness distributions were determined by the determination of the layer thicknesses.
3. Results 3.1. Spot movement The utilisation of the process combination of steered arc and modified pulsed arc process caused an acceleration of the spot movement. The movement occurred circularly around the permanent magnet. The diversion of the spots
Fig. 2. Comparison of spot movement during modified pulsed arc process and combination with steered arc process (I G = 80 A, I P = 400 A, f P = 00 Hz, and t P = 0.7 ms).
636
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
0,8
Table 1 Samples for average speed of spot movement
Random arc process
Steered arc process
Modified pulsed arc process Process combination
– – – – – – – – 200 200 200 200 200 200 200 200
t pulse [s]
80 100 120 140 80 100 120 140 0.5 0.6 0.7 0.8 0.5 0.6 0.7 0.8
I base [A]
– – – – – – – – 80 80 80 80 80 80 80 80
I pulse [A]
– – – – – – – – 400 400 400 400 400 400 400 400
Average speed of spots (titanium) [m/s] 7.6 8.7 7.7 9.7 17.9 19.5 22.0 22.5 10.3 11.1 17.6 15.5 19.6 19.2 22.5 24.2
Average speed of spots (chrome) [m/s] 4.1 5.2 7.2 8.0 11.3 14.8 16.3 12.2 9.4 12.2 11.8 10.6 16.0 13.1 13.5 15.2
probe 0°
0,4 0,0 20
0,8
iion in A
f pulse [Hz]
40
60
80
100
probe 22,5° 0,4 0,0 0,8 0
20
40
60
80
100
probe 45° 0,4 0,0 0
20
40
60
80
100
t in ms Fig. 3. Shape of ion current for combination of steered arc and modified pulsed arc process (Ti: I G = 80 A, I P = 400 A, t P = 0.6 ms, f P = 200 Hz, V BIAS = V probe = 100 V, and p = 1 Pa).
during the current pulse was superimposed by the circular d.c. trace. It resulted in modifications concerning the trace and the speed of the individual spots. A fan-shaped movement of spots into the direction of the motion of the circular d.c. trace was observed at titanium and chrome as target materials (Fig. 2). Since the spot moved predominantly towards the direction of this circular orbit, the area on which an abrasion occurs was reduced. Measured speeds of spot movement can be taken from Table 1.
observed. This is a reference for a change of the spatial emission characteristics of the modified pulsed arc process through the process combination (Table 2). The focussing of the plasma as it is known for the modified pulsed arc process is weakened by the permanent magnetic field. The observation of the ion current values, cf. Fig. 3, reveals a considerable difference during the pulse phases for the 458 probe. This is caused by the rotation of the spots along the target. Therefore, the change in distance between the current probes and the arc spots results directly in a pulsation of the measured current values.
3.2. Ion current measurements with single probes
3.3. Layer qualities
The average ion current was reduced for probe 08 and 22.58 for the process combination in arrangement with a steered arc process. At the probe 458 an increase of the average ion current (up to 17% for a TiAl target) was
In Fig. 4 shapes of the layer thickness on a 22 cm substrate are represented. The film thickness uniformity for the process combination resembles to the uniformity for the steered arc process. The focussing of the plasma, which is
Table 2 Comparison of average ion current related to arc current (I arc, average = 120 A, I G = 80 A, I P = 400 A, t P = 0.7 ms, f P = 200 Hz, V BIAS = V probe = 100 V, p = 1 Pa, and distance target–probe: 140 mm) I ionMW / I arcMW [mA/A] Random arc
Steered arc
Modified PA
Combination
Modified pulsed arc process related to random arc [%]
Steered arc related to random arc [%]
Combination related to steered arc [%]
TiN Probe 08 Probe 22.58 Probe 458
0.281 0.172 0.153
0.188 0.146 0.154
0.411 0.256 0.163
0.187 0.148 0.171
51.7 49.5 6.6
30.7 15.1 0.6
0.6 1.8 11.2
TiAlN Probe 08 Probe 22.58 Probe 458
0.237 0.145 0.135
0.149 0.138 0.123
0.326 0.179 0.132
0.138 0.136 0.144
37.6 23.6 2.8
37.1 4.9 9.1
7.6 1.3 17.4
CrN Probe 08 Probe 22.58 Probe 458
0.401 0.328 0.184
0.191 0.182 0.141
0.693 0.527 0.215
0.172 0.174 0.143
72.8 60.7 16.7
52.5 44.4 23.3
9.9 4.7 1.0
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
thin film thickness in µm
9
steered arc lower droplet ratios depending on the chosen pulse parameters were determined.
random arc steered arc (1) modified pulsed arc process (2) combination of processes (1+2)
8 7
637
6
4. Discussion
5 4 3 2 1 -10 -8
-6
-4
-2
0
2
4
6
8
10
position on the substrate in cm Fig. 4. Film thickness uniformity for CrN for various used coating technologies with equal average arc current and coating time (TiN: I arc, avg J 120 A, V BIAS = 200 V, and p = 1 Pa).
typical for the modified pulsed arc process, is lost through the effect of the magnetic field. A measurement of the film thicknesses showed an increase of the deposition rate for CrN by approx. 18% for the process combination in the arrangement to the steered arc. The evaluation of the droplets showed that in case of application of the process combination, as also during the pure steered arc process, there are no droplets larger than 10 Am (Table 3). The area part of the droplets on the entire surface was most of the time less than half during the steered arc process in comparison with the random arc. A comparison of the process combination with the modified pulsed arc process showed also a decrease of the area part of the droplets. According to the chosen pulse parameters of the arc current the droplet ratio was decreased between 8% and 75% through application of the process combination for the chosen example with chrome as a target material. Even with a comparison of the process combination with the
The directed movement of the spots influences the plasma qualities. The average ion current, which was measured with the stationary probes, was influenced by the choice of the used process. The average ion current at the probes by 08 and 22.58 was reduced for a comparison of the process combination with a steered arc process. At the probe 458 an increase of the average ion current is observed through the order of the probe and the circular movement of the spots. The resulting layer thickness uniformity for the process combination resembles qualitatively to the process for the layer thickness uniformity from the steered arc. The evaluation of the droplets showed that in case of the process combination, as also during the pure steered arc process, there are no droplets larger than 10 Am. According to the chosen pulse parameters the droplet ratio was reduced through the process combination.
5. Conclusions An accelerated movement of the spots is caused by a combination of steered arc and modified pulsed arc process. The spots move around the circular d.c. trace which is forced by the permanent magnet deflected to both sides (fan-shaped movement) during the current pulses. Through an increase of the speed of the spots and consequently the avoidance of local overheating the process combination in comparison with the modified pulsed arc process results in droplet reduction.
Table 3 Comparison of droplet distribution for the modified pulsed arc process and the combination of steered arc and modified pulsed arc process (CrN: V BIAS = 200 V, p = 1 Pa, and t coat = 20 min)
Modified pulsed arc
Combination
f p (Hz)
t p (s)
I G (A)
I p (A)
200 200 200 200 80 80 80 80 200 200 200 200 80 80 80 80
0.5 0.6 0.7 0.8 0.8 0.8 0.8 0.8 0.5 0.6 0.7 0.8 0.8 0.8 0.8 0.8
80 80 80 80 80 80 80 80 80 80 80 80 80 80 80 80
400 400 400 400 400 500 600 700 400 400 400 400 400 500 600 700
Percentage of area
Total
0.5–1 Am
1.01–2 Am
2.01–5 Am
5.01–10 Am
10.01–20 Am
20.01–30 Am
0.40 0.39 0.43 0.50 0.42 0.41 0.43 0.43 0.60 0.54 0.66 0.34 0.33 0.26 0.51 0.65
2.82 2.37 3.26 3.66 2.91 3.10 2.76 2.88 3.52 3.13 3.79 1.89 1.71 1.42 2.64 3.47
4.51 2.55 4.77 6.32 3.68 4.10 3.89 3.32 2.48 2.24 2.44 1.27 1.12 0.92 1.59 2.21
1.48 1.15 1.80 2.32 1.19 1.42 1.56 0.99 0.36 0.24 0.30 0.17 0.25 0.22 0.41 0.36
1.39 0.18 0.48 0.94 0.90 0.19 0.51 0.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.22 0.00 0.70 0.56 0.00 0.00 0.00 0.37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
10.82 6.64 11.43 14.29 9.10 9.22 9.15 8.27 6.96 6.15 7.19 3.66 3.41 2.81 5.15 6.69
638
E. Hettkamp, H. Mecke / Surface & Coatings Technology 200 (2005) 634–638
The combination with the steered arc leads to a modification of the spatial emission characteristic for the modified pulsed arc process. The strong plasma focussing is weakened by the effect of the magnetic field. It could be observed that a process combination of steered arc with the modified pulsed arc process leads to a modification of the layer thickness uniformity with respect to the consideration of single processes.
Acknowledgements This work has been supported by the German Research Foundation.
References [1] P.J. Martin, Cathodic arc deposition, Handbook of Thin Film Process Technology, A1.4, The Institute of Physics, 1995, p. 1. [2] M. Ellrodt, Doctoral thesis, Otto-von-Guericke-University of Magdeburg, 1997. [3] B. Schultrich, P. Siemroth, J. Vetter, O. Zimmer, Vak. Forsch. Prax. 1 (1998) S.37. [4] E. Ertqrk, H.-J. Heuvel, H.-G. Dederichs, Ind.-Anz. 21 (1989) S.22. [5] H.-D. Steffens, L. Cronj7ger, R. Kopp, DqnnschichtechnologienVortr7ge zum Statusseminar, 1990, p. S.465. [6] G.E. Kim, J.-L. Meunier, F. Ajersch, IEEE Trans. Plasma Sci. 23 (6) (1995) S.1001. [7] K. Keutel, E. Hettkamp, H. Fuchs, Thin Solid Films 458 (2004) S.173.