Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C19/00—Alloys based on nickel or cobalt
  • C22C19/03—Alloys based on nickel or cobalt based on nickel
• • 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
  • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
  • C23C14/34—Sputtering
  • C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
  • C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
• • 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
  • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
  • C23C14/54—Controlling or regulating the coating process

Definitions

• the present invention relates to a nickel alloy sputtering target enabling the formation of a thermally stable silicide (NiSi) film, having favorable plastic workability to the target, and which is particularly effective in the manufacture of a gate electrode material (thin film), as well as to the manufacturing method thereof.
• NiSi thermally stable silicide
• NiSi film in the salicide process is attracting attention.
• Nickel in comparison to cobalt, is characterized in that it is capable of forming a silicide film with less consumption of silicon during the salicide process.
• NiSi, as with a cobalt silicide film is characterized in that the increase of fine wire resistance pursuant to the miniaturization of wiring is unlikely to occur.
• NiSi it can easily make a phase transition to the more stable NiSi 2 , and there is a problem of the boundary roughness becoming aggravated and highly resistive. Moreover, there are other problems in that the film is easily coagulated and excessive formation of suicides may occur.
• TiC, TiW, TiB, WB 2 , WC, BN, AlN, Mg 3 N 2 , CaN, Ge 3 N 4 , TaN, TbNi 2 , VB 2 , VC, ZrN, ZrB and the like are also disclosed as the cap film (c.f. Japanese Patent Laid-Open Publication No. H7-38104).
• NiSi is easily oxidized even within the silicide material, large irregularities are formed on the boundary area of the NiSi film and Si substrate, and a connection leak will occur.
• Ni may be sputtered with argon gas only without containing nitrogen gas, subsequently sputtering the cap film of TiN, and thereafter injecting N ion in Ni film in order to add N in the Ni film (c.f. Japanese Patent Laid-Open Publication No. H9-153616).
• a semiconductor device and the manufacturing method are disclosed, and the combination of primary metals: Co, Ni, Pt or Pd and secondary metals: Ti, Zr, Hf, V, Nb, Ta or Cr is described. In the Examples, the Co—Ti combination is used.
• Cobalt has a lower capability of reducing the silicon oxide film in comparison to titanium, and the silicide reaction will be inhibited if there is natural oxide film existing on the silicon substrate or polysilicon film surface upon accumulating cobalt. Further, the heat resistance properties are inferior to a titanium silicide film, and problems have been indicated in that the heat upon accumulating the silicon oxide film as the interlayer film after the completion of the salicide process causes the coagulation of the cobalt disilicide (CoSi 2 ) film and the resistance to increase (c.f. Japanese Patent Laid-Open Publication No. H11-204791 (U.S. Pat. No. 5,989,988)).
• the purity was roughly up to 4N excluding gas components, and the oxygen was high at roughly 100 ppm.
• An object of the present invention is to provide a nickel alloy sputtering target, and the manufacturing technology thereof, enabling the formation of a thermally stable silicide (NiSi) film, unlikely to cause the coagulation of films or excessive formation of silicides, having few generation of particles upon forming the sputtered film, having favorable uniformity and superior in the plastic workability to the target, and which is particularly effective for the manufacture of a gate electrode material (thin film).
• NiSi thermally stable silicide
• the present inventors discovered that a target enabling the formation of a thermally stable silicide (NiSi) film, having few generation of particles during sputtering, having favorable uniformity and superior in plastic workability by adding specific metal elements to high purity nickel.
• NiSi thermally stable silicide
• the present invention provides:
• the target of the present invention is made to be a high purity nickel alloy ingot by performing electrolytic refining to rough Ni (up to roughly 4N), removing the metal impurity components, and further refining this with EB melting in order to obtain a high purity nickel ingot. Then, this ingot and high purity tantalum are subject to vacuum melting to prepare a high purity nickel alloy ingot.
• the cold crucible melting method employing a water-cooled copper crucible is suitable.
• This alloy ingot is cast, rolled and subject to other processes to form a plate shape, and ultimately subject to heat treatment at a recrystallization temperature about 500° C. to 950° C. to prepare a target.
• the analytical values of this representative high purity nickel target are shown in Table 1.
• Element (wtppm) Li ⁇ 0.001 Ag ⁇ 0.01 Be ⁇ 0.001 Cd ⁇ 0.01 B 0.02 In ⁇ 0.05 F ⁇ 0.01 Sn 0.2 Na ⁇ 0.01 Sb ⁇ 0.01 Mg 0.57 Te ⁇ 0.01 Al 0.14 I ⁇ 0.01 Si 2.7 Cs ⁇ 0.01 P ⁇ 0.01 Ba ⁇ 0.005 S 0.02 La ⁇ 0.005 Cl ⁇ 0.01 Ce ⁇ 0.005 K ⁇ 0.01 Pr ⁇ 0.005 Ca ⁇ 0.01 Nd ⁇ 0.005 Sc ⁇ 0.001 Sm ⁇ 0.005 Ti 0.24 Eu ⁇ 0.005 V 0.01 Gd ⁇ 0.005 Cr 0.02 Tb ⁇ 0.005 Mn 0.12 Dy ⁇ 0.005 Fe 1 Ho ⁇ 0.005 Co 0.66 Er ⁇ 0.005 Ni Matrix Tm ⁇ 0.005 Cu 0.13 Yb ⁇ 0.005 Zn ⁇ 0.01 Lu ⁇ 0.005 Ga ⁇ 0.01 Hf ⁇ 0.01 Ge ⁇ 0.05 Ta 10.01 As ⁇ 0.05 F ⁇ 0.01 Sn 0.2
• the additive amount of tantalum is 0.5 to 10 at %, more preferably 1 to 5 at %. If the additive amount is too small, the thermal stability of the nickel alloy layer cannot be improved. If the additive amount is too great, the film resistance will become so large that it will be inappropriate, and there is a problem in that the amount of intermetallic compounds will increase and make the plastic processing difficult, and the generation of particles during sputtering will also increase.
• the inevitable impurities excluding gas components 100 wtppm or less, and more preferably 10 wtppm or less.
• Final heat treatment is performed at a recrystallization temperature about 500° C. to 950° C. to form a substantial recrystallization texture. If the heat treatment temperature is less than 500° C., sufficient recrystallization texture cannot be obtained. Further, the permeability and maximum magnetic permeability cannot be improved.
• the average crystal grain size of the target is 80 ⁇ m or less.
• a final heat treatment exceeding 950° C. is not preferable as this will enlarge the average crystal grain size.
• the average crystal grain size is enlarged, the variation of the crystal grain size will increase, and the uniformity will deteriorate.
• Rough Ni (up to roughly 4N) was subject to electrolytic refining, metal impurity components were removed, this was further refined with EB melting in order to obtain a high purity nickel ingot, and this ingot and high purity tantalum were subject to vacuum melting in order to manufacture a high purity nickel alloy ingot.
• the cold crucible melting method employing a water-cooled copper crucible was used.
• This alloy ingot was cast, rolled and subject to other processes to form a plate shape, and ultimately subject to heat treatment at a recrystallization temperature about 500° C. to 950° C. to prepare a target.
• the manufacturing conditions of the target namely, the Ta amount, purity, oxygen content, and heat treatment temperature conditions, as well as the characteristics of the target and deposition; namely, the initial magnetic permeability, maximum magnetic permeability, average crystal grain size, variation of the crystal grain size, particle amount, and uniformity are shown in Table 2.
• Example 1 series has a Ta amount of 1.68 at %
• Example 2 series has a Ta amount of 3.48 at %
• Example 3 series has a Ta amount of 7.50 at %.
• TABLE 2 Initial Maximum Heat Treatment Magnetic Magnetic Particles Ta Volume Oxygen Conditions Permea- Permea- Average Grain Variation (0.3 ⁇ m or Uniformity (at %) Purity (wtppm) (° C.) ⁇ 1 hr bility bility Size ( ⁇ m) (%) more/in 2 ) (%, 3 ⁇ )
• Example 1-1 1.68 5N 35 500 62 103 Non-recrystal- — 23 8 lization Found Example 1-2 1.68 5N 25 600 103 142 Non-recrystal- — 18 11 lization Found Example 1-3 1.68 5N ⁇ 10 650 121 165 17.3 9.6 15 7 Comparative 1.68 3N5 80 650 118 161 7.1 8.2 113 5
• Example 1-1 Comparative 1.68 4N 75 650
• Examples 1-1 to 1-3, Examples 2-1 to 2-4 and Examples 3-1 to 3-2 in which the Ta amount, purity, oxygen content, and heat treatment temperature conditions are within the scope of the present invention had an initial magnetic permeability of 50 or more, a maximum magnetic permeability of 100 or more, an average crystal grain size of 80 ⁇ m or less, the variation of the crystal grain size was small, the particle amount (0.3 ⁇ m or more/in 2 ) was also small, and the uniformity (%, 3 ⁇ ) was also a small value.
• Example 1-1 since the heat treatment temperature was slightly low in Example 1-1, Example 1-2 and Example 2-1, there were some non-recrystallized textures, but since the existence thereof was small, the characteristics were not affected.
• the manufacture process was the same as the foregoing Examples, and the additive amount of Ta was also the same, but the conditions of purity, oxygen content and heat treatment temperature were changed as shown in Table 2 upon manufacturing the target.
• the characteristics of the target and deposition namely, the initial magnetic permeability, maximum magnetic permeability, average crystal grain size, variation of the crystal grain size, particle amount, and uniformity were measured and observed.
• Comparative Example 1 series has a Ta amount of 1.68 at %
• Comparative Example 2 series has a Ta amount of 3.48 at %
• Comparative Example 3 series has a Ta amount of 7.50 at %.
• Comparative Examples 1-1 and 1-2 has significant amounts of oxygen, and, since the purity is low, there was a problem in that many particles were generated. Since the heat treatment temperature is too low in Comparative Examples 1-3 and 1-4, the initial magnetic permeability and maximum magnetic permeability could not be improved, and this could not be recrystallized, or large amounts of non-recrystallized textures existed.
• a nickel alloy sputtering target containing a prescribed amount of tantalum in nickel yields a superior effect in that it enables the formation of a thermally stable silicide (NiSi) film, is unlikely to cause the coagulation of films or excessive formation of suicides, has few generation of particles upon forming the sputtered film, has favorable uniformity and is superior in the plastic workability to the target, and is particularly effective for the manufacture of a gate electrode material (thin film).

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Physical Vapour Deposition (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32708970

Family Applications (1)

Country Status (6)

Cited By (14)

Families Citing this family (3)

Citations (20)

Family Cites Families (3)

• 2003
  • 2003-01-10 JP JP2003004685A patent/JP4466902B2/ja not_active Expired - Lifetime
  • 2003-10-06 WO PCT/JP2003/012777 patent/WO2004063420A1/ja active Application Filing
  • 2003-10-06 US US10/540,638 patent/US20060037680A1/en not_active Abandoned
  • 2003-10-06 KR KR1020057012585A patent/KR100660731B1/ko active IP Right Grant
  • 2003-10-06 CN CNA2003801085083A patent/CN1735707A/zh active Pending
  • 2003-10-09 TW TW092128062A patent/TWI227279B/zh not_active IP Right Cessation

Patent Citations (23)

Also Published As

Similar Documents

Legal Events