Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/0021—Reactive sputtering or evaporation
  • C23C14/0036—Reactive sputtering
  • C23C14/0094—Reactive sputtering in transition mode
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
  • C23C14/0021—Reactive sputtering or evaporation
  • C23C14/0036—Reactive sputtering
  • C23C14/0042—Controlling partial pressure or flow rate of reactive or inert gases with feedback of measurements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
  • H01J37/32—Gas-filled discharge tubes
  • H01J37/32431—Constructional details of the reactor
  • H01J37/3244—Gas supply means
  • H01J37/32449—Gas control, e.g. control of the gas flow
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
  • H01J37/32—Gas-filled discharge tubes
  • H01J37/34—Gas-filled discharge tubes operating with cathodic sputtering
  • H01J37/3411—Constructional aspects of the reactor

Definitions

• the present invention relates to a method for regulating DC, MF or HF excited reactive sputtering processes.
• Plasma sputtering is an established technology for the coating of substrates, especially with ceramic or other multi-component functional layers.
• Sputtering, in particular reactive magnetron sputtering is based on the sputtering of metallic targets in a reactive atmosphere with the aim of growing the desired compound with the desired microstructure and phase composition on the substrate at a high rate.
• Another method is the regulation of reactive processes for the deposition of oxidic layers in accordance with a 0 2 partial pressure measurement using a lambda probe by adapting the discharge power or the discharge current.
• a corresponding concept is known from EP 0 795 623 AI.
• control loops can be designed to be significantly more robust with regard to industrial use, since the complex optical measurement technology for analyzing Cd Cd p *
• Tr d tr ⁇ d iQ P- x Tr d tr ⁇ d iQ P- x.
• the temperature measuring element is electrically heated with several measuring points so that a constant temperature is reached along the temperature measuring element.
• the electrical power to be used then represents a measure of the gas flow flowing through the mass flow controller.
• the method according to the invention and the device according to the invention are suitable for controlling direct current (DC), medium frequency (MF) or high frequency (HF) sputtering processes.
• the DC, MF or HF discharge power can also be regulated, so that an even better maintenance of the operating point is ensured in the transition mode.
• Fig. 3 experimental data on the hysteresis curves for uncontrolled operation and for flow control according to a partial pressure measurement • using a lambda probe.
• the reactive MF magnetron sputtering of Nb 2 Os layer systems was investigated.
• 1 shows the sputtering system 1 used shown. This contains a double cathode arrangement with two conventional magnetron cathodes 2a, 2b, each with a target format of 488 x 88 mm 2 .
• the sputtering gas and the reactive gas are added separately via conventional gas distributors, which are symbolized by the reference numerals 4 and 5, via conventional mass flow controllers from the MKS company.
• a mass flow controller of the 1259 series from the manufacturer MKS was used as the mass flow controller.
• the conventional magnetron cathodes 2a and 2b are supplied with power by an MF generator and adapter unit 3.
• a plasma cloud 7 is built up between the cathodes 2a and 2b and the substrate 6 during magnetron sputtering.
• the reactive gas partial pressure was measured with a lambda probe, to which the process gas is fed via a special gas supply.
• the control loop was implemented on the basis of a proportional-integral-differential controller (PID controller).
• PID controller proportional-integral-differential controller
• the PID control loop for controlling the 0 2 flow according to the 0 2 partial pressure was designed on the basis of model calculations for simulating the target coverage, which also took into account the dynamic behavior of the target coverage.
• FIG. 2 shows a typical example of modeling reactive sputtering according to this approach.
• the calculated reactive gas partial pressure as a function of the reactive gas flow is plotted here as part of a dynamic simulation of the reactive sputtering process in the Larson model.
• a PID algorithm was used for the control, the mo- dell parameters were adapted to the experimental parameters.
• the dashed curve shows the stationary solution of the Larson differential equation, which enables a simplified description of the hysteresis problem in reactive sputtering.
• the dashed S curve when the reactive gas flow is increased, stable working points up to point B are reached (metallic mode, metal mode).
• the solid curve now shows the calculated course of the reactive gas partial pressure, whereby the time dependence of the target coverage was simulated in simple models.
• the coating process was stabilized using a PID controller, the parameters of which were optimally adapted to the experimental model.
• Argon pressure of 1.1 mTorr was used.
• the same reference numerals as in FIG. 2 have been used for the same curve elements.
• the final regulation was carried out in accordance with the partial pressure measurement using a Lainbda probe.
• Curves 10 and 11 again show the simulated data, which correspond to those in FIG. 2.
• Curve 12 is now not a simulated curve but an experimentally measured control trajectory. It can be seen that by means of the control according to the invention using a lambda probe and a conventional mass flow controller it is actually possible to stabilize the sputtering process in the transition area (transition mode).

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7636548

Family Applications (1)

Country Status (4)

Cited By (5)

Citations (4)

Family Cites Families (1)

• 2001
  • 2001-03-27 WO PCT/EP2001/003443 patent/WO2001073151A1/de active IP Right Grant
  • 2001-03-27 EP EP01938052A patent/EP1268872B2/de not_active Expired - Lifetime
  • 2001-03-27 AU AU2001263815A patent/AU2001263815A1/en not_active Abandoned
  • 2001-03-27 DE DE50100613T patent/DE50100613D1/de not_active Expired - Lifetime

Patent Citations (4)

Non-Patent Citations (3)

Also Published As

Similar Documents

Legal Events