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• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
  • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
  • H01L21/321—After treatment
  • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
  • H01L21/32133—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only
  • H01L21/32135—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
  • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
  • H01L21/3105—After-treatment
  • H01L21/311—Etching the insulating layers by chemical or physical means
  • H01L21/31144—Etching the insulating layers by chemical or physical means using masks
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
  • H01L21/67005—Apparatus not specifically provided for elsewhere
  • H01L21/67011—Apparatus for manufacture or treatment
  • H01L21/67098—Apparatus for thermal treatment
  • H01L21/67109—Apparatus for thermal treatment mainly by convection
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
  • H01L21/67005—Apparatus not specifically provided for elsewhere
  • H01L21/67011—Apparatus for manufacture or treatment
  • H01L21/67155—Apparatus for manufacturing or treating in a plurality of work-stations
  • H01L21/6719—Apparatus for manufacturing or treating in a plurality of work-stations characterized by the construction of the processing chambers, e.g. modular processing chambers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
  • H01L21/683—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping
  • H01L21/6838—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere for supporting or gripping with gripping and holding devices using a vacuum; Bernoulli devices
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/02104—Forming layers
  • H01L21/02107—Forming insulating materials on a substrate
  • H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
  • H01L21/02227—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process
  • H01L21/0223—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by oxidation, e.g. oxidation of the substrate
  • H01L21/02244—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by oxidation, e.g. oxidation of the substrate of a metallic layer
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
  • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
  • H01L21/321—After treatment
  • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
  • H01L21/32139—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer using masks

Definitions

• Embodiments of the present disclosure generally relate to methods and apparatus for using alkyl amines for the selective removal of metal nitrides.
• Metal nitride materials such as titanium nitride (TiN) and tantalum nitride (TaN) are commonly used in the semiconductor industry for many semiconductor applications, such as a masking material or as a barrier material.
• TiN titanium nitride
• TaN tantalum nitride
• selectively removing a metal nitride masking material without harming other structures is very difficult.
• the problem of selectively removing a metal nitride masking material without harming other structures becomes even more difficult where solution based or plasma based approaches are not feasible and/or desirable.
• the inventors have developed improved methods and apparatus for removing a metal nitride selectively with respect to exposed or underlying dielectric or metal layers.
• a method of etching a metal nitride layer atop a substrate includes: (a) oxidizing a metal nitride layer to form a metal oxynitride layer (MNi -x O x ) at a surface of the metal nitride layer, wherein M is one of titanium or tantalum and x is an integer from 0.05 to 0.95; and (b) exposing the metal oxynitride layer (MNi -x O x ) to a process gas, wherein the metal oxynitride layer (MN -x O x ) reacts with the process gas to form a volatile compound which desorbs from the surface of the metal nitride layer.
• MNi -x O x metal oxynitride layer
• a method of etching a titanium nitride layer atop a substrate includes: exposing a titanium nitride layer to a process gas formed by vaporizing a process solution comprising diethylamine and water, wherein the titanium nitride layer reacts with the process gas to form a volatile compound which desorbs from the surface of the titanium nitride layer.
• an apparatus for etching a metal nitride layer atop a substrate apparatus for etching a metal nitride layer atop a substrate includes: a reactor body comprising a processing volume to hold a liquid process solution, a body flange at a first end, and a first heater embedded within or coupled to the reactor body at a second end opposite the first end to heat the liquid process solution; a reactor lid comprising a lid flange at a first end configured to mate with the body flange; a circumferential clamp configured to clamp the reactor body to the reactor lid at the lid flange and the body flange; a vacuum chuck embedded within the reactor lid and configured to hold a substrate within the processing volume such that a metal nitride layer disposed on the substrate faces a bottom of the processing volume; a second heater embedded within or coupled to the reactor lid and configured to heat the substrate; and an exhaust system coupled to the reactor body to remove process byproducts from the processing volume.
• Figure 1 depicts a flowchart of a method of etching a metal nitride layer atop a substrate in accordance with some embodiments of the present disclosure.
• Figures 2A-C depicts the stages of etching a metal nitride layer atop a substrate in accordance with some embodiments of the present disclosure.
• Figure 3 depicts a cross-sectional view of an apparatus suitable to perform methods for etching a metal nitride layer atop a substrate in accordance with some embodiments of the present disclosure
• inventive methods and apparatus for etching a metal nitride selectively with respect to exposed or underlying dielectric or metal layers are provided herein.
• the inventive methods described herein advantageously provide an innovative method of etching a metal nitride, utilized as a masking material, selectively with respect to exposed or underlying dielectric or metal layers, for example BLACK DIAMOND ® dielectric material available from Applied Materials, Inc. of Santa Clara, California (hereinafter "Black Diamond” or "BD”) or silicon dioxide layers (e.g. SiOx).
• Black Diamond or “BD”
• the inventive methods described herein may also be used in other semiconductor manufacturing applications where etching a metal nitride may be necessary.
• an amine-based solution is vaporized and applied to a metal nitride material to selectively etch the metal nitride material from the top of structures without harming, for example, underlying or exposed Black Diamond, silicon dioxide, and/or copper (Cu) structures.
• Figure 1 is a flow diagram of a method 100 of etching a metal nitride layer atop a substrate in accordance with some embodiments of the present disclosure.
• Figures 2A-2C are illustrative cross-sectional views of the substrate during different stages of the processing sequence of Figure 1 in accordance with some embodiments of the present disclosure.
• the inventive methods may be performed in a suitable reactor vessel, such as the reactor vessel discussed below with respect to Figure 3.
• Figure 3 depicts a cross-sectional view of a reactor vessel 300 suitable for performing method 200.
• the reactor vessel 300 is a closed loop controlled system using materials for the wetted parts of the reactor vessel 300 that are compatible with chemicals utilized in method 200 described below.
• the reactor vessel 300 depicted in Figure 3 comprises a reactor body 302 and a reactor lid 304.
• the reactor body 302 and the reactor lid 304 comprise suitable openings for the addition of sensors, power, and vacuum inputs as described below.
• the reactor body 302 comprises a processing volume 306.
• the processing volume 306 holds a suitable liquid process solution 318 used in the method 100 described below. In some embodiments, the processing volume 306 can hold up to about 200 to about 300 ml of a suitable liquid process solution 318.
• the reactor body 302 and the reactor lid are made of material suitable for withstanding the temperature and pressures utilized in the method 200 described below.
• the reactor body 302 and the reactor lid are made of stainless steel (SST) material coated with, for example Teflon or Magnaplate 10K. The coating can be selected based on the compatibility with the chemicals, temperatures, and pressures utilized in the method 200.
• the reactor body 302 comprises a body flange 322 at a first end 324.
• the reactor lid 304 comprises a lid flange 326 at a first end 328 configured to mate with the body flange 322.
• the body flange 322 is clamped with the lid flange 326 and having a leak proof O-ring 330 seal.
• the body flange 322 has a chamfered back-surface 356.
• the lid flange 326 has a chamfered back-surface 358.
• the body flange 322 and the lid flange 326 are mated by a circumferential clamp 332 tightened by a bolt 334 around the chamfered back-surfaces 356, 358.
• Cooling channels 336 are added in the vicinity of the O-ring 330 to protect the O-ring 330 from high temperatures. Cooling channels 336 are also provided on the top of the reactor lid 304 to maintain the outer reactor lid 304 temperature below about 70°C for safety purposes. Suitable inlets 344 and outlets 346 are coupled to the cooling channels 336 to supply and remove a cooling fluid such as water from the cooling channels 336. The outside walls 338 of the reactor body 302 are covered with an insulation jacket 340 to avoid condensation of process gases and protection from high temperature surfaces. [0018] A vacuum chuck 308, coupled to a vacuum source 360, is embedded within the reactor lid 304 and configured to hold the substrate 314 within the processing volume 306. The vacuum chuck 308 holds the substrate 314 such that the metal nitride layer disposed on the substrate 314 faces the bottom 316 of the processing volume 306.
• the liquid process solution 318 within the processing volume 306 is heated using, for example, a first heater 310 embedded within or coupled to the reactor body 302 at a second end 362.
• the first heater 310 is coupled to a suitable power supply (not shown).
• the first heater 310 heats the liquid process solution 318 to a temperature sufficient to vaporize the solvent.
• the substrate 314 is heated using, for example, a second heater 312 embedded within or coupled to the reactor lid 304.
• the second heater 312 is coupled to a suitable power supply (not shown).
• the first heater 310 and the second heater 312 may be at the same temperature.
• the first heater 310 and the second heater 312 may be at different temperatures.
• the first heater may be at a temperature of about 25 degrees Celsius to about 300 degrees Celsius.
• the second heater is at a higher temperature than the first heater to avoid condensation of vapors onto the substrate 314.
• the second heater 312 is at a temperature that is about 10 to about 15 degrees greater than the first heater temperature.
• the reactor lid 304 is clamped to a top portion of the reactor body 302 to seal the processing volume 306.
• the reactor body 302 is also heated using for example heating coils within the reactor body 302. Heating the reactor body 302 prevents condensation of vapors onto the interior surface walls 320 of the processing volume 306.
• the liquid process solution 318 is injected inside the processing volume 306 through an opening 342 in the reactor body 302.
• a manual valve 364 is used to drain out the liquid process solution 318 from the processing volume 306.
• a closed loop controlled exhaust system 348 coupled to the reactor body 302 takes a feedback from a pressure transducer 350 setting to trigger a pneumatic valve 352 to releases byproducts of the method 200 to, for example a scrubber, via the overpressure line 354.
• a temperature loop feedback is maintained by thermocouples 354 & an over temperature switch 366 with heater controller.
• the method 100 begins at 102, and as depicted in Figure 2A, by oxidizing a metal nitride layer 204 atop a substrate 202.
• the substrate 202 may be any suitable substrate, such as a semiconductor wafer. Substrates having other geometries, such as rectangular, polygonal, or other geometric configurations may also be used.
• the substrate 202 may include a first layer 216.
• the first layer 216 may be a base material of the substrate 202 (e.g., the substrate itself), or a layer formed on the substrate.
• the first layer 216 may be a layer suitable for forming a feature within the first layer 216.
• the first layer 216 may be a dielectric layer, such as silicon oxide (Si02), silicon nitride (SiN), a low-k material, or the like.
• the low-k material may be carbon-doped dielectric materials (such as carbon-doped silicon oxide (SiOC), BLACK DIAMOND® dielectric material available from Applied Materials, Inc. of Santa Clara, California, or the like), an organic polymer (such as polyimide, parylene, or the like), organic doped silicon glass (OSG), fluorine doped silicon glass (FSG), or the like.
• the first layer 216 may be a copper layer.
• the metal nitride layer 204 is titanium nitride (TiN) or tantalum nitride (TaN).
• the metal nitride layer 204 is deposited using any suitable deposition process known in the semiconductor manufacturing industry, such as a physical vapor deposition (PVD) process or a chemical vapor deposition (CVD) process.
• the metal nitride layer may be a masking layer used for forming features, such as vias or trenches in underlying layers.
• Oxidation of the metal nitride layer 204 forms a metal oxynitride layer (MNi -x O x ) 208 at a surface 214 of the metal nitride layer 204, where M is one of titanium or tantalum and x is an integer from 0.05 to 0.95.
• the metal nitride layer 204 is oxidized by exposing the metal nitride layer 204 to an oxygen-containing gas 206.
• the oxygen containing gas is oxygen (O2) gas or ozone (O3) gas or combination thereof.
• the oxygen-containing gas 206 is provided at a flow rate of about 2 seem to about 20 seem for about 2 to about 30 seconds.
• the metal oxynitride layer (MN-i. ⁇ ) 208 is exposed to a process gas 210.
• the reaction of the process gas 210 and the metal oxynitride layer (MNi -x O x ) 208 forms a volatile compound 212 atop the metal nitride layer 204 which desorbs from the surface 214 of the metal nitride layer 204.
• the volatile compound 212 desorbs from the surface 214 of the metal nitride layer 204 at the temperature at which the process gas 210 is formed, accordingly a separate anneal process is unnecessary to desorb the volatile compound 212.
• the process gas 210 is produced by heating a liquid process solution within the reactor vessel 300 to at least the boiling point of the liquid process solution.
• the process solution comprises an etchant precursor of secondary amines having the formula Ri R 2 NH wherein Ri and R 2 can be an alkyl group such as methyl, ethyl, propyl, or butyl.
• the etchant precursor is diethylamine, tert-butylamine, ethyldenediamine, triethylamine, dicyclohexylamine, hydroxylamine, dipropylamine, dibutylamine, butylamine, isopropylamine, or propylamine.
• the liquid process solution is heated to a temperature of at least the boiling point of the liquid process solution or in some embodiments to a temperature of at least above the boiling point of the liquid process solution.
• the maximum temperature to which the liquid process solution is heated is limited by the decomposition temperature of the selected etchant precursor molecule.
• the process solution comprising diethylamine, which has a boiling point of about 55 degrees Celsius is heated to a temperature of about 80 to about 175 degrees Celsius.
• the process solution comprising dicyclohexylamine, having a boiling point of about 255 degrees Celsius is heated to a temperature of up to about 300 degrees Celsius.
• the inventors have also observed that increasing the volume of the etchant precursor, for example from about 5 ml to about 30 ml, and utilizing higher temperatures to vaporize the process solution (though still limited by decomposition temperature of the selected etchant precursor molecule), results in an increase in the pressure within the reactor vessel 300 which improves the etch rate of the metal nitride layer 204.
• the inventors have observed that a pressure range of about 1 atmosphere (atm) to about 10 atm, for example about 7 atm improves the etch rate of the metal nitride layer 204.
• the metal oxynitride layer (MNi -x O x ) 208 is exposed to the process gas 210 for about 10 to 1200 seconds, for example for about 10 to about 300 seconds, for example for about 60 to about 1200 seconds.
• the oxidation of the metal nitride layer 204 is done within the reactor vessel 300 without exposure to the oxygen-containing gas as described above (i.e., in-situ oxidation).
• the metal nitride layer is not exposed to an initial oxygen-containing gas.
• the liquid process solution comprises a mixture of the etchant precursor and water.
• the liquid process solution consists of, or consists essentially of, a mixture of the etchant precursor and water.
• the liquid process solution comprises about 0.1 wt. % to about 5 wt % of water and the balance etchant precursor.
• the process gas 210 shown in Figure 2B can advantageously oxidize and etch the metal nitride layer 204 in a single step and furthermore improve the etch rate of the metal nitride layer 204 as compared to an initial oxidation of the metal nitride layer 204 oxidation via exposure to the oxygen- containing gas.
• performing an in-situ oxidation results in an metal nitride layer 204 etch rate of about 3 to 4 angstroms/minute, whereas a separate oxidation step results in a lower metal nitride layer 204 etch rate.
• the method 100 can be repeated to etch the metal nitride layer 204 to a predetermined thickness. For example, in some embodiments, the method 100 is repeated to completely, or substantially completely, etch the metal nitride layer 204 without damaging the underlying first layer 216.

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• 2016
  • 2016-02-25 KR KR1020177026904A patent/KR20170121243A/ko not_active Withdrawn
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