US20150145106A1 - ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS - Google Patents

ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS Download PDF

Info

Publication number
US20150145106A1
US20150145106A1 US14/571,968 US201414571968A US2015145106A1 US 20150145106 A1 US20150145106 A1 US 20150145106A1 US 201414571968 A US201414571968 A US 201414571968A US 2015145106 A1 US2015145106 A1 US 2015145106A1
Authority
US
United States
Prior art keywords
low
dielectric component
polyimide aerogel
aerogel film
dielectric
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/571,968
Inventor
Nicholas Anthony Zafiropoulos
Paul Nahass
Roxana Trifu
Redouane Begag
Wendell E. Rhine
Wenting Dong
Shannon Olga White
George L. Gould
Alaric Naiman
Roger Sinta
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aspen Aerogels Inc
Original Assignee
Aspen Aerogels Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aspen Aerogels Inc filed Critical Aspen Aerogels Inc
Priority to US14/571,968 priority Critical patent/US20150145106A1/en
Assigned to ASPEN AEROGELS, INC. reassignment ASPEN AEROGELS, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GOULD, GEORGE, NAHASS, PAUL, BEGAG, REDOUANE, RHINE, WENDELL E, SINTA, ROGER, DONG, WENTING, NAIMAN, ALARIC, WHITE, SHANNON, TRIFU, ROXANA, ZAFIROPOULOS, NICHOLAS A
Publication of US20150145106A1 publication Critical patent/US20150145106A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/52Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
    • H01L23/522Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
    • H01L23/532Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body characterised by the materials
    • H01L23/5329Insulating materials
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02107Forming insulating materials on a substrate
    • H01L21/02109Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02112Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
    • H01L21/02118Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer carbon based polymeric organic or inorganic material, e.g. polyimides, poly cyclobutene or PVC
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L79/00Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen or carbon only, not provided for in groups C08L61/00 - C08L77/00
    • C08L79/04Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
    • C08L79/08Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02107Forming insulating materials on a substrate
    • H01L21/02109Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02112Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
    • H01L21/02123Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon
    • H01L21/02126Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing silicon the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02107Forming insulating materials on a substrate
    • H01L21/02109Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
    • H01L21/02203Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates the layer being porous
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104Forming layers
    • H01L21/02107Forming insulating materials on a substrate
    • H01L21/02225Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
    • H01L21/0226Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process
    • H01L21/02282Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31Treatment 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
    • H01L21/3105After-treatment
    • H01L21/31058After-treatment of organic layers
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001Technical content checked by a classifier
    • H01L2924/0002Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Materials and methods for manufacturing electronic devices and semiconductor components using low dielectric materials comprising polyimide based aerogels are described. Additional methods for manipulating the properties of the dielectric materials and affecting the overall dielectric property of the system are also provided.

Description

  • This Application is a continuation of U.S. patent application Ser. No. 13/358,462, filed on Jan. 25, 2012; which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/435,840, filed on Jan. 25, 2011 under 35 U.S.C. §119(e); which applications are incorporated by reference herein in their entirety.
  • FIELD OF THE INVENTION
  • The present disclosure relates generally to the field of manufacture of electronic devices. In particular, the present invention relates to the manufacture of integrated circuits containing low dielectric constant material.
  • BACKGROUND
  • As electronic devices become smaller, there is a continuing desire in the electronics industry to increase the circuit density in electronic components, e.g., integrated circuits, circuit boards, multichip modules, chip test devices, and the like without degrading electrical performance, e.g., crosstalk or capacitive coupling, known as RC delay, and also to increase the speed of signal propagation in these components. One method of accomplishing these goals is to reduce the dielectric constant of the interlayer insulating material used in the components that separate the signal carrier species. A method for reducing the dielectric constant of such interlayer insulating material is to incorporate within the insulating film very small, uniformly dispersed pores or voids. Since air and other gasses have the lowest dielectric constants, their incorporation significantly lowers the overall dielectric constant. Most materials are limited in the amount of air pockets they can contain and still maintain structural integrity.
  • A variety of organic and inorganic dielectric materials are known in the art as insulating films in the manufacture of electronic devices, particularly integrated circuits. Suitable inorganic dielectric materials include silicon dioxide and organo polysilicas. Suitable organic dielectric materials include thermosets such as polyimides, polyarylene ethers, polyarylenes, polycyanurates, polybenzazoles, benzocyclobutenes and the like. Methods of providing porous dielectrics have focused on incorporating particles into the dielectric which are later removed using heat processes. In general, porous dielectric materials are prepared by first incorporating a removable particles into a B-staged dielectric material, disposing the B-staged dielectric material containing the removable particle onto a substrate, curing the B-staged dielectric material and then removing the particle to form pores in the dielectric material. For example, U.S. Pat. No. 5,895,263 (Carter et al.) discloses a process for forming an integrated circuit containing porous organo polysilica dielectric material. U.S. Pat. No. 6,093,636 (Carter et al.) discloses a process for forming an integrated circuit containing porous thermoset dielectric material. Gallagher in U.S. Pat. No 6,596,467B2 also describes the use of pore generating materials in dielectrics. In each of these patents, the amount of pores that can be created is limited due in part to the amount of heat needed to depolymerize the particles while maintaining the strength and integrity of the composition. Because there is a limit as to how much of the dielectric can contain pores, the value of the dielectric can not reach below about 2 without compromising the dielectric layer. Also, in the Carter patents, the process described requires the step of forming the porous dielectric material prior to any subsequent processing steps, while in the Gallagher patent the dielectric is fully or partially covered with metal or other materials hindering the removal of the by-products of the depolymerized particles.
  • There is thus a need for processes for manufacturing electronic devices including porous dielectric materials that have dielectric constants below around 2.0 while maintaining the structure integrity of the material.
  • SUMMARY OF THE DISCLOSURE
  • It has been found that processes to provide polyimide aerogels as well as hybrid organic-inorganic aerogels are suitable for the manufacture of low k dielectric materials for use in electronic devices.
  • In a first embodiment of the current application for patent is disclosed and claimed a method for producing a polyimide based low dielectric material suitable for an electronic device including the steps of disposing on a substrate a pre-sol composition including a polyamic acid pre-sol, a catalyst and a polar, aprotic solvent, curing the pre-sol composition to form a wet-gel matrix material, washing the wet-gel with a solvent to replace the polar, aprotic solvent, and removing the solvent using super critical carbon dioxide to provide an aerogel, wherein the dielectric constant of the polyimide aerogel is between about 1.1 and about 2.0.
  • In a second embodiment of the current application for patent is disclosed and claimed is the method of the above embodiment further including the step of flash exposing either the wet-gel or the aerogel to one or more polar, protic solvents or other anti-solvent to provide an increased density gradient at the surfaces of the aerogel, this step being applied prior to washing the wet-gel with a solvent to replace the polar, aprotic solvent.
  • In a third embodiment of the current application for patent is disclosed and claimed is the method of the first embodiment, wherein the step of removing the solvent using super critical carbon dioxide is accompanied by pressure cycling in a drying vessel used in the removal process to provide an increase density gradient at the surfaces of the aerogel.
  • In a fourth embodiment of the current application for patent is disclosed and claimed are methods of the above embodiments wherein the surfaces of the aerogel are capped with non-porous dielectric materials deposited using at least one of chemical vapor deposition, atomic layer deposition, physical layer deposition, or spin-on materials, wherein the spin-on materials are at least on of glasses, siloxanes, silsesquioxanes, polyimides, poly(aryl esters), polycarbonates, poly(arylene ethers), polyaromaic hydrocarbons, poly(perfluorinated hydrocarbons, polycyanurates, polybenzoxazoles, parylenes, polycycloolefins or benzocyclobutenes, annealing the surfaces of the aerogels by treatment with an annealing plasma, or providing a seed layer for metallization.
  • In a fifth embodiment of the current application for patent is disclosed and claimed are methods of the above embodiments wherein the substrate comprises predefined patterns into which the pre-sol compositions are applied and includes the step of removing the material which pre-defined the patterns after the aerogel is obtained providing an aerogel pattern.
  • In a sixth embodiment of the current application for patent is disclosed and claimed are methods of the above embodiments wherein the pre-sol composition is a hybrid pre-sol including at least one tetraalkoxysilane which may optionally be partially hydrolyzed at least one bis-trialkoxysilane diimide, a selected amount of water, and a gelation catalyst, or the hybrid pre-sol may be admixed with the polyamic acid pre-sol.
  • In a seventh embodiment of the current application for patent is disclosed and claimed are methods of the above embodiments in which the aerogel obtained from each process is patterned using standard lithographic and etching techniques.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 shows a synthetic scheme for preparing a polyimide.
  • FIG. 2 shows the relationship between aerogel density and dielectric constant.
  • FIG. 3 shows the relationship between aerogel density and compressive strength comparing polyimide aerogels to silica aerogels.
  • FIG. 4 shows scanning electron microscope images of a silica aerogel and a polyimide aerogel prepared by the methods of the current disclosure.
  • FIGS. 5 a-5 f are a cross section of an electronic device showing the dielectric aerogels of the current disclosure.
  • FIG. 6 is a cross section of an electronic device showing multiple layers of the dielectric aerogels of the current disclosure.
  • DETAILED DESCRIPTION
  • As used herein, the conjunction “and” is intended to be inclusive and the conjunction “or” is not intended to be exclusive unless otherwise indicated. For example, the phrase “or, alternatively” is intended to be exclusive.
  • Aerogels are a class of materials formed by removing a mobile interstitial solvent phase from the pores of a gel structure supported by an open-celled polymeric material at a temperature and pressure above the solvent critical point. By keeping the solvent phase above the critical pressure and temperature during the entire solvent extraction process, strong capillary forces generated by liquid evaporation from very small pores that cause shrinkage and pore collapse are not realized. Aerogels typically have low bulk densities, (about 0.15 g/cc or less, preferably about 0.03 to 0.3 g/cc), very high surface areas, (generally from about 400 to 1,000 m2/g and higher, preferably about 700 to 1000 m2/g), high porosity, (about 95% and greater, preferably greater than about 97%), and relatively large pore volume (more than about 3.8 mL/g, preferably about 3.9 mL/g and higher). The combination of these properties in an amorphous structure gives the lowest thermal conductivity values (9 to 16 mW/m·K at 37° C. and 1 atmosphere of pressure) for any coherent solid material.
  • One of the most attractive properties of aerogels is their low dielectric constant. Aerogels, for example, have the lowest dielectric constant (k) for a solid, near that of air, 1.0. Additionally, aerogels have exceptionally high dielectric resistivity and strength; they can insulate very high voltages and have low dielectric loss at microwave frequencies. Aerogels have been explored as next generation materials for energy storage, low power consumption, and high-speed electronics. Silica-based aerogels have dominated research for electronic applications. Standard sol-gel chemistry plus a benign drying process yield aerogels with a solid structured network of particles and pores fractions of the wavelength of visible light. The governing features of an aerogel's dielectric properties are primarily the large volume fraction of trapped gas in the pores and the high concentration of adsorbed molecules on the very large internal surface area, most often physisorbed water molecules.
  • In order to achieve ultra low-k (ULK) dielectrics (k<1.9), materials must be highly porous. Silica aerogels can be made with greater than 90% porosity, yielding dielectric constants less than 1.5. However, the high porosity that gives silica aerogels their remarkable dielectric properties yields a material with very poor mechanical strength, making them too fragile for practical processing technologies in chip manufacturing.
  • It has surprisingly been found that a process for applying polyimide aerogel precursor compositions in electronic devices leads to polyimide aerogels, when further processed, with dielectric constants below about 2.0 while maintaining high structural integrity, determined by their high compression modulus. The process includes deposing on a substrate a pre-sol composition comprising a polyamic acid pre-sol, a catalyst and a polar, aprotic solvent. The composition may be disposed by any of a number of well known processes such as, for example, spin coating, curtain coating, slot coating, roller coating, inkjet coating, lithographic coating and dip coating.
  • The composition to be coated is a polyimide pre-sol material. The polyimide pre-sol is a polyamic acid or a partially imidated form thereof, obtained by the admixture of a dianhydride and a diamine, which is also known as a B-stage material, as shown in FIG. 1.
  • The diamine starting material include, for example, 4,4′-diaminodiphenylether, 3,3′-dimethyl-4,4′-diaminodiphenylether, 3,3′-diethoxy-4,4′-diaminodiphenylether, p-phenylenediamine, 2,6diaminopyridine, 3,6-diaminopyridine, 2,5-diaminopyridine and 3,4-diaminopyridine, but others may also be used. More than one diamine may be used as starting materials in the disclosed process.
  • The dianhydride starting materials include, for example, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,3,3′,4′-biphenyltetracarboxylic anhydride, 2,3,3′,4′- and 3,3′,4,4′-biphenyltetracarboxylic anhydride, 2,3,3′,4′- and 3,3′,4,4′-biphenyltetracarboxylic anhydride. pyromellitic acid, 3,3′,4,4′-benzophenonetetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4dicarboxyphenyl)ether, bis(3,4-dicarboxyphenyl)thioether. The starting materials for making B-staged polyamic acid is not limited only to dianhydrides but can include, for example, the free acids, their salts or their esters. More than one dianhydride, or derivative, may be used as starting materials in the disclosed process.
  • Polar, aprotic solvents used in the preparation of the pre-sol composition, include, but not limited to, N-methyl-2-pyrrolidone (NMP), pyridine, N,N-dimethylacetamide (DMAC),N,N-dimethylformamide, and dimethylsulfoxide
  • A catalyst is admixed with the pre-sol composition in order to complete the imidization process to provide the polymeric polyimide wet gel, wherein the solvent is still present. While heat may be used to obtain the polyimide, the current process provides for the retention of solvent in the gel to maintain pores. It has been found that heat high enough to imidize the polyamic acid will drive off the solvent and cause the pores to collapse. Typical catalysts known in the art to aid in the imidization process include, for example, amines, such as for example, pyridine and dehydrating agents such as, for example, acetic acid. The pre-sol coating is then cured at low temperature, between about room temperature and 60° C., for a period of time, between about 1 to about 24 hours, depending on the nature and amount of the catalyst used, to provide the polyimide wet-gel.
  • The resulting gel material may be washed in a suitable solvent to replace the reaction solvent present in the wet-gel. Such solvents may be linear monohydric alcohols with 1 or more aliphatic carbon atoms, dihydric alcohols with 2 or more carbon atoms, branched alcohols, cyclic alcohols, alicyclic alcohols, aromatic alcohols, polyhydric alcohols, ethers, ketones, cyclic ethers or their derivative. This process may be followed by removal of the solvent using super critical CO2.
  • Drying of the wet gel can be accomplished using a variety of methods to obtain the desired aerogel porosity and structure. Methods of drying gels to obtain aerogels or xerogels are well known in the art. U.S. Pat. Nos. 5,275,796 and 5,395,805 describe supercritical drying to produce silica aerogels. U.S. Pat. No. 6,670,402 teaches drying via rapid solvent exchange of solvent inside wet gels using supercritical CO2 by injecting supercritical, rather than liquid, CO2 into an extractor that has been pre-heated and pre-pressurized to substantially supercritical conditions or above to produce aerogels. U.S. Pat. No. 5,962,539 describes a process for obtaining an aerogel from a polymeric material that is in the form a sol-gel in an organic solvent, by exchanging the organic solvent for a fluid having a critical temperature below a temperature of polymer decomposition, and supercritically drying the fluid/sol-gel. U.S. Pat. No. 6,315,971 discloses processes for producing gel compositions comprising: drying a wet gel comprising gel solids and a drying agent to remove the drying agent under drying conditions sufficient to minimize shrinkage of the gel during drying.
  • One example of drying the wet-gel/wet-film of the current disclosure uses supercritical conditions of CO2 including for example, first substantially exchanging the solvent present in the porosity of the gels by liquid CO2 and in the second step heating the autoclave (in which the wet gel or the substrate coated with the wet-gel is placed) beyond the critical temperature of CO2 which is 31.06° C. and increasing the pressure to a pressure greater than about 1070 psig. In an alternative way, the drying of aerogels is carried out directly by heating the autoclave beyond the critical temperature of CO2. The system is kept at these conditions for at least an hour while a continuous flow of CO2 at the above described conditions is maintained to ensure that essentially all the solvent have been removed from the gel. After that, the autoclave is depressurized slowly to atmospheric pressure.
  • In another example of the drying process the wet-gel is not processed through the solvent washing step but is exposed to the super critical CO2 process containing a small percentage of a solvent, or solvents, that are reasonably miscible with super critical CO2 such as those that can be used in the washing step listed above, in an amount, for example, between 1 and 10% of the CO2. Generally polar protic/aprotic solvents are suitable for this purpose.
  • In some embodiments of the current disclosure both the washing step and the critical CO2 containing solvent steps are used while in some other embodiments, the washing step can be avoided.
  • The resulting materials are called aerogels and have densities between 0.05 and 0.40 g/cc. As shown on FIG. 2, the density of the aerogel is in essentially direct proportion to the dielectric constant. The polyimides of the current invention also have high mechanical strength as shown in FIG. 3. For example, the polyimide aerogel with a density of 0.30 g/cc has a dielectric constant of approximately 1.4 with and a compression modulus of approximately 15,000 psi. In certain embodiments of the present invention, polyimide aerogels with varying compression modulus from 5000 psi to 25000 psi are employed. The silica aerogel of similar density and dielectric constant has a compression modulus of only approximately 1000 psi. Thus it can be seen that the process to provide low-k dielectric polyimide aerogels results in materials that can be used in electronic devices as well as in the processes used to make the electronic devices. FIG. 4 shows the surface of a polyimide aerogel prepared by the currently disclosed methods, shown in comparison to a silica aerogel prepared by standard techniques for their preparation.
  • In many electronic devices dielectrics are used to insulate various signal carrying materials and components. In many of the processes the dielectrics are exposed to various plating processes such as chemical vapor deposition of conductive materials which are later processed into signal carrying lines and interconnections. It may thus be desirable to provide a barrier layer to prevent materials from infiltrating the pores of the dielectric aerogel and thus compromise a portion of its dielectric strength. The current disclosure provides for a number of methods of provide such a barrier. The term “capping” is used herein to describe the process of providing such barrier.
  • In another embodiment, surface of the polyimide aerogel film facing away from the substrate may be treated to make it denser. Polyimide aerogel thin films are treated with predetermined quantities of one or more suitable solvents in liquid or vapor form to modify the surface sufficient enough to substantially seal the surface pores of the film. The duration, temperature, pressure and direction of such solvent exposure/treatment may be varied to control the amount of surface sealing required to substantially maintain the effective dielectric constant of the whole system. Solvents suitable for the surface densification process are linear monohydric alcohols with 7 or more aliphatic carbon atoms, dihydric alcohols with 7 or more carbon atoms, branched alcohols, cyclic alcohols, alicyclic alcohols, aromatic alcohols and other high-boiling point alcohols as well as polyhydric alcohols, ethers, cyclic ethers or their derivative
  • In another embodiment, surface densification is achieved during super critical CO2 drying. During that process the pressure of the drying vessel is cycled, to induce localized stresses on the pores of a gel, thereby creating a gradient in density across the thickness direction. For example, during the super critical drying described above the pressure can be cycled between 100 psi and 1070 psi a pre-determined number of times. Alternatively, ultrasonic or similar energy sources may be used in the drying process to achieve a local pressure cycling at the surface of the polyimide aerogel thin films.
  • Other methods are disclosed to “cap” the dielectric polyimide aerogel. The term “cap” used herein refers to a barrier layer which retards materials from subsequent processes from seeping into the porous dielectric to the extent that the dielectric constant is retained to about 75% or more of the original dielectric constant. These include traditional capping processes such as chemical vapor deposition (CVD), atomic layer deposition (ALD), physical vapor deposition and spin-on organics or inorganics. The spin-on materials are glasses, siloxanes, silsesquioxanes, polyimides, poly(aryl esters), polycarbonates, poly(arylene ethers), polyimides, polyaromatic hydrocarbons, poly(perfluorinated hydrocarbons, polybenzoxazoles, parylenes, polycycloolefins, benzocyclobutenes, or combinations thereof. The capping materials applied by the vapor deposition and atomic layer deposition include metal oxides such as, for example Al2O3, TiO2, SnO2, ZnO, HfO2 as well as other oxides, metal nitrides, such as InN, TaN, WN, NbN or their carbides, metal sulfides, such as for example, ZnS or metals, such as Ru, Ir, or Pt. These examples are non-restrictive as other material known in the art can be applied in the similar manner as described above.
  • Also disclosed are methods wherein the surfaces of the dielectric polyimide aerogel may also be sealed by sintering processes such as, for example, treatment with plasma to for a shell-like barrier. The surface of the aerogel film away from the substrate is treated with laser radiation to seal the surface, such as, for example, an infrared laser that melts the surface of the film causing it to self-seal the pores on the surface of the film.
  • A further method for capping is disclosed wherein a seed layer is placed on the surfaces of the polyimide aerogel film away from the substrate. This seed layer provides metallization or nucleation sites on the surface. The polyimide aerogel film is then placed in a metallization bath and a metal coating over the pores is achieved, thus providing a barrier.
  • The disclosed capping methods may be applied to the dielectric polyimide aerogel after drying with super critical CO2 or after the surface has been densified, as disclosed above.
  • The polyimide aerogel materials of the several embodiments of the present invention are in the form of films with thicknesses ranging from 10 nm to 100,000 nm. Thickness may be controlled by the amount of pre-sol composition dispensed on to the substrate.
  • The pre-sol composition may be applied to a surface such as a silicon wafer which may or may not contain other layers, a dielectric surface, a glass surface and the like. The pre-sol can then be processed to form the dielectric polyimide aerogel. The aerogel may then be patterned using standard patterning techniques such as, for example, patterning a photoresist followed by removal of the polyimide aerogel. Other techniques include applying an etch stop, followed by photoresist patterning, etching the polyimide and optionally removing the etch stop. The aerogel may be capped or densified at any of the stages of the described processes.
  • The pre-sol composition may further be applied to substrates such as structures, or patterned surfaces. For example, the pre-sol composition is applied into spaces, trenches, holes and the like, provided by a photoresist pattern. The pre-sol is gelled and the photoresist is removed to leave behind a pattern of polyimide aerogel structures. These structures can be subsequently capped as described above. Thus obtained article may be exposed to all typical processes in the manufacture of electronic devices or semiconductor fabrication.
  • The pre-sol composition may be composed of a hybrid pre-sol, containing at least one tetraalkoxysilane which may optionally be partially hydrolyzed, at least one bis-trialkoxysilane diimide, a selected amount of water, and a gelation catalyst, in which case the provided aerogel is a dielectric hybrid aerogel containing siloxane moieties with imide cross-links. The composition could be a blend of both the hybrid pre-sol and the polyamic acid pre-sol, in which case the dielectric aerogel is a combination of polyimide and hybrid aerogel structure. The hybrid aerogel compositions useful in this embodiment include the ones disclosed in U.S. patent application Ser. No. 13/299,677 filed on Nov. 18, 2011 which is incorporated by reference herein.
  • Although the present invention has been shown and described with reference to particular examples, various changes and modifications which are obvious to persons skilled in the art to which the invention pertains are deemed to lie within the scope and contemplation of the subject matter set forth in the appended claims.
  • Referring to FIG. 5, a substrate 10 is coated with a pre-sol composition 12 in FIG. 5 a. The pre-sol composition is processed to form polyimide aerogel film 14 on substrate 10 in FIG. 5 b. Pattern 16 in FIG. 5 c are provided using lithographic techniques involving photoresists followed by etching of the exposed polyimide aerogel and removal of the photoresist. The aerogels are shown “capped” 18 in FIG. 5 d followed by the incorporation of signal line 20 in FIG. 5 e. Often the metallization process results in completely plating the whole surface as shown in FIG. 5 f. In order to remove the excess copper a process called chemical mechanical polishing is used. This requires that the materials subjected to this process maintain structure stability in order to withstand the polishing process. FIG. 6 shows a series of stacks using the methods of the current disclosure including the versatility of burying a signal line 22.

Claims (20)

What is claimed is:
1. A low-k dielectric component suitable for an electronic device comprising: a substrate; a polyimide aerogel film coating at least a portion of the substrate; and a barrier layer coating at least a portion of the polyimide aerogel film away from the substrate; wherein the barrier layer comprises at least one non-porous, low-k dieletric material.
2. The low-k dielectric component of claim 1, wherein the polyimide aerogel film has a density between about 0.05 and about 0.40 g/cc.
3. The low-k dielectric component of claim 1, wherein the polyimide aerogel film has a dielectric constant between about 1.1 and about 2.0.
4. The low-k dielectric component of claim 1, wherein the polyimide aerogel film has compression modulus between about 2000 psi and about 25000 psi.
5. The low-k dielectric component of claim 1, wherein the polyimide aerogel film is formed from a pre-sol composition comprising: a polyamic acid pre-sol, a catalyst and a polar, aprotic solvent.
6. The low-k dielectric component of claim 5, wherein the polyamic acid is obtained by admixing a dianhydride material and a diamine material.
7. The low-k dielectric component of claim 6, wherein the dianhydride material comprises: 3,3′,4,4′-biphenyltetracarboxylic dianhydride; 2,3,3′,4′-biphenyltetracarboxylic anhydride; 2,3,3′,4′- or 3,3′,4,4′-biphenyltetracarboxylic anhydride; 2,3,3′,4′- or 3,3′,4,4′-biphenyltetracarboxylic anhydride; pyromellitic acid; 3,3′,4,4′-benzophenonetetracarboxylic acid; 2,2-bis(3,4-dicarboxyphenyl)propane; bis(3,4-dicarboxyphenyl)sulfone; bis(3,4dicarboxyphenyl)ether; bis(3,4-dicarboxyphenyl)thioether; or combinations thereof.
8. The low-k dielectric component of claim 6, wherein the diamine material comprises: 4,4′-diaminodiphenylether; 3,3′-dimethyl-4,4′-diaminodiphenylether; 3,3′-diethoxy-4,4′-diaminodiphenylether; phenylenediamine; 2,6-diaminopyridine; 3,6-diaminopyridine; 2,5-diaminopyridine; 3,4-diaminopyridine; or combinations thereof.
9. The low-k dielectric component of claim 5, wherein the pre-sol composition comprises a hybrid pre-sol, comprising:
a) at least one tetra-, tri-, di- and/or mono- alkoxysilane which may optionally be partially hydrolyzed,
b) at least one bis-bi-, or trialkoxysilane diimide,
c) a selected amount of water, and
d) a gelation catalyst.
10. The low-k dielectric component of claim 1, wherein the polyimide aerogel film is coated on the substrate in a pattern.
11. The low-k dielectric component of claim 1, wherein the at least one non-porous, low-k dieletric material comprises glasses, siloxanes, silsesquioxanes, polyimides, poly(aryl esters), polycarbonates, poly(arylene ethers), polyimides, polyaromatic hydrocarbons, poly(perfluorinated hydrocarbons, polybenzoxazoles, parylenes, polycycloolefins, benzocyclobutenes, or combinations thereof.
12. The low-k dielectric component of claim 1, wherein the barrier layer is coated onto the polyimide aerogel film by chemical vapor deposition, atomic layer deposition, physical vapor deposition, spin-on deposition, or combinations thereof.
13. A low-k dielectric component suitable for an electronic device comprising: a substrate; a polyimide aerogel film coating at least a portion of the substrate; and at least one non-porous, low-k dieletric material coating at least a portion of the polyimide aerogel film away from the substrate.
14. The low-k dielectric component of claim 13, wherein the polyimide aerogel film has a density between about 0.05 and about 0.40 g/cc.
15. The low-k dielectric component of claim 13, wherein the polyimide aerogel film has a dielectric constant between about 1.1 and about 2.0.
16. The low-k dielectric component of claim 13, wherein the polyimide aerogel film has compression modulus between about 2000 psi and about 25000 psi.
17. The low-k dielectric component of claim 13, wherein the polyimide aerogel film is formed from a pre-sol composition comprising: a polyamic acid pre-sol, a catalyst and a polar, aprotic solvent.
18. The low-k dielectric component of claim 13, wherein the polyimide aerogel film is coated on the substrate in a pattern.
19. The low-k dielectric component of claim 13, wherein the at least one non-porous, low-k dieletric material comprises glasses, siloxanes, silsesquioxanes, polyimides, poly(aryl esters), polycarbonates, poly(arylene ethers), polyimides, polyaromatic hydrocarbons, poly(perfluorinated hydrocarbons, polybenzoxazoles, parylenes, polycycloolefins, benzocyclobutenes, or combinations thereof.
20. The low-k dielectric component of claim 13, wherein the non-porous, low-k dieletric material is coated onto the polyimide aerogel film by chemical vapor deposition, atomic layer deposition, physical vapor deposition, spin-on deposition, or combinations thereof.
US14/571,968 2011-01-25 2014-12-16 ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS Abandoned US20150145106A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/571,968 US20150145106A1 (en) 2011-01-25 2014-12-16 ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US201161435840P 2011-01-25 2011-01-25
US13/358,462 US8945677B2 (en) 2011-01-25 2012-01-25 Electronic device manufacture using low-k dielectric materials
US14/571,968 US20150145106A1 (en) 2011-01-25 2014-12-16 ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US13/358,462 Continuation US8945677B2 (en) 2011-01-25 2012-01-25 Electronic device manufacture using low-k dielectric materials

Publications (1)

Publication Number Publication Date
US20150145106A1 true US20150145106A1 (en) 2015-05-28

Family

ID=46544363

Family Applications (2)

Application Number Title Priority Date Filing Date
US13/358,462 Active 2032-06-30 US8945677B2 (en) 2011-01-25 2012-01-25 Electronic device manufacture using low-k dielectric materials
US14/571,968 Abandoned US20150145106A1 (en) 2011-01-25 2014-12-16 ELECTRONIC DEVICE MANUFACTURE USING LOW-k DIELECTRIC MATERIALS

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US13/358,462 Active 2032-06-30 US8945677B2 (en) 2011-01-25 2012-01-25 Electronic device manufacture using low-k dielectric materials

Country Status (1)

Country Link
US (2) US8945677B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11753517B2 (en) 2019-12-12 2023-09-12 Raytheon Company Dispensable polyimide aerogel prepolymer, method of making the same, method of using the same, and substrate comprising patterned polyimide aerogel

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8231692B2 (en) * 2008-11-06 2012-07-31 International Business Machines Corporation Method for manufacturing an electronic device
US10707082B2 (en) * 2011-07-06 2020-07-07 Asm International N.V. Methods for depositing thin films comprising indium nitride by atomic layer deposition
US9666514B2 (en) * 2015-04-14 2017-05-30 Invensas Corporation High performance compliant substrate
KR102460463B1 (en) 2015-06-22 2022-10-31 인텔 코포레이션 Image Tone Reversal by Dielectric Using Bottom-Up Crosslinking for Back End of Line (BEOL) Interconnects
US10724132B2 (en) * 2017-04-04 2020-07-28 General Electric Company Method of preparing aerogel particles and aerogel coated component
GB2573810B (en) 2018-05-18 2021-02-24 Graphene Composites Ltd Protective shield and shield wall
US10665545B2 (en) * 2018-09-19 2020-05-26 Taiwan Semiconductor Manufacturing Co., Ltd. Semiconductor devices, semiconductor packages and methods of forming the same
CN114592353B (en) * 2020-12-07 2024-02-02 财团法人纺织产业综合研究所 Non-woven fabric membrane material for electronic element and preparation method thereof
CN113698601A (en) * 2021-09-06 2021-11-26 黄山金石木塑料科技有限公司 Method for synthesizing high-performance polyimide resin with assistance of ultrasonic microwave method
EP4261187A1 (en) 2022-04-14 2023-10-18 Taiwan Aerogel Technology Material Co., Ltd. Aerogel and preparation method therefor

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6399669B1 (en) * 1998-09-17 2002-06-04 Matsushita Electric Industrial Co., Ltd. Porous material and a method for producing the same
US6424038B1 (en) * 2001-03-19 2002-07-23 Taiwan Semiconductor Manufacturing Co., Ltd Low dielectric constant microelectronic conductor structure with enhanced adhesion and attenuated electrical leakage
US8067478B1 (en) * 2006-10-19 2011-11-29 The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration Process for preparing polymer reinforced silica aerogels

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60119730A (en) * 1983-11-30 1985-06-27 インタ−ナショナル ビジネス マシ−ンズ コ−ポレ−ション Method of forming polymer film
RU2002113291A (en) * 1999-10-21 2004-03-27 Эспен Системз, Инк. (Us) METHOD FOR ACCELERATED PRODUCTION OF AEROGEL
EP3656802A1 (en) * 2002-07-22 2020-05-27 Aspen Aerogels Inc. Polyimide aerogels, carbon aerogels, and metal carbide aerogels and methods of making same
TW562822B (en) * 2002-09-03 2003-11-21 Chang Chun Plastics Co Ltd Organic-inorganic hybrid film material and its preparation

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6399669B1 (en) * 1998-09-17 2002-06-04 Matsushita Electric Industrial Co., Ltd. Porous material and a method for producing the same
US6424038B1 (en) * 2001-03-19 2002-07-23 Taiwan Semiconductor Manufacturing Co., Ltd Low dielectric constant microelectronic conductor structure with enhanced adhesion and attenuated electrical leakage
US8067478B1 (en) * 2006-10-19 2011-11-29 The United States Of America As Represented By The Administrator Of National Aeronautics And Space Administration Process for preparing polymer reinforced silica aerogels

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Meador, Mary Ann B., et al., "Improvements to the Synthesis of Polyimide Aerogels," ACS Spring National Meeting 2011, Anaheim, CA; Mar. 20-26, 2011, 34 pages. *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11753517B2 (en) 2019-12-12 2023-09-12 Raytheon Company Dispensable polyimide aerogel prepolymer, method of making the same, method of using the same, and substrate comprising patterned polyimide aerogel

Also Published As

Publication number Publication date
US20120189782A1 (en) 2012-07-26
US8945677B2 (en) 2015-02-03

Similar Documents

Publication Publication Date Title
US8945677B2 (en) Electronic device manufacture using low-k dielectric materials
CN100477106C (en) Semiconductor device fabrication method
Zhao et al. Review of polymer materials with low dielectric constant
JP4374567B2 (en) Ultraviolet curing treatment for porous low dielectric constant materials
KR101177591B1 (en) Ultraviolet assisted pore sealing of porous low k dielectric films
US5801092A (en) Method of making two-component nanospheres and their use as a low dielectric constant material for semiconductor devices
JP2005503672A (en) Plasma curing method for porous low dielectric constant materials
TW200408535A (en) Low dielectric materials and methods for making same
JP2004538637A (en) Plasma curing of MSQ porous low K film material
JP5007511B2 (en) Exposure light shielding film forming material, multilayer wiring, manufacturing method thereof, and semiconductor device
US6764718B2 (en) Method for forming thin film from electrically insulating resin composition
JP2002289604A (en) Circuit board and its manufacturing method
JPH1092804A (en) Manufacture of porous dielectric film
KR100455886B1 (en) Semiconductor device fabrication method
US6447846B2 (en) Electrically insulating thin-film-forming resin composition and method for forming thin film therefrom
TWI233215B (en) Semiconductor device and method of manufacturing same
JP2007073914A (en) Porous thin film, manufacturing method therefor, and semiconductor device using it
JP3210601B2 (en) Semiconductor device and manufacturing method thereof
US6602801B2 (en) Method for forming a region of low dielectric constant nanoporous material
KR102160552B1 (en) Manufacturing method of insulator film and insulator film making apparatus
JP2003031566A (en) Composition for forming low-permittivity insulation film, insulation film forming method using the same, and electronic component having the insulation film obtained by the method
JP4459096B2 (en) Manufacturing method of semiconductor device
Wu et al. Nanoporous organosilicate glass films via chemical vapor deposition onto colloidal crystal templates
US8716150B1 (en) Method of forming a low-K dielectric film
JP3328545B2 (en) Method for manufacturing semiconductor device

Legal Events

Date Code Title Description
AS Assignment

Owner name: ASPEN AEROGELS, INC., MASSACHUSETTS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ZAFIROPOULOS, NICHOLAS A;NAHASS, PAUL;TRIFU, ROXANA;AND OTHERS;SIGNING DATES FROM 20120126 TO 20120210;REEL/FRAME:034879/0300

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION