Aug.  1,  2019  1  US 2019/0235380 Al  NEGATIVE TYPE PHOTOSENSITIVE RESIN  COMPOSITION, PHOTOSENSITIVE RESIST  FILM, PATTERN FORMING METHOD,  CURED FILM, AND METHOD OF  PRODUCING CURED FILM  Solution to Problem  TECHNICAL FIELD  BACKGROUND ART  CITATION LIST  Patent Literature  SUMMARY OF INVENTION  Technical Problem  [0014]  According to a fifth aspect of the present invention,  there is provided a method of producing a cured film,  including: a step of forming a photosensitive resin film on a  support using the negative type photosensitive resin com› position according to the first aspect or the photosensitive  resist film according to the second aspect; and a step of  curing the photosensitive resin film to obtain a cured film.  [0007]  However, in a case where the thickness of the cured  film is reduced using the photosensitive resin composition  described in PTL 1 and miniaturization of the hollow sealing  structure is attempted, the hardness of the cured thin film  against a processing pressure under a high temperature (150°  C. to 200°  C.) condition during molding is insufficient, and  thus it is difficult to maintain the hollow sealing structure.  [0013]  According to a fourth aspect of the present inven› tion, there is provided a cured film which is obtained by  curing the negative type photosensitive resin composition  according to the first aspect.  [0006]  [PTL 1] Japanese Unexamined Patent Application,  First Publication No. 2008-250200  [0012]  According to a third aspect of the present inven› tion, there is provided a pattern forming method including:  a step of forming a photosensitive resin film on a support  using the negative type photosensitive resin composition  according to the first aspect or the photosensitive resist film  according to the second aspect; a step of exposing the  photosensitive resin film; and a step of developing the  exposed photosensitive resin film to form a negative type  pattern.  [0011]  According to a second aspect of the present inven› tion, there is provided a photosensitive resist film which is  obtained by laminating a base film, a photosensitive resin  film formed using the negative type photosensitive resin  composition according to the first aspect, and a cover film in  that order.  [0010]  [In the formulae, R 601  to R$^{04 }$each independently  represent an aryl group which may have a substituent or a  fluorine atom. R 605  represents a fluorinated alkyl group  which may have a substituent or a fluorine atom. A plurality  ofR$^{605}$’s may be the same as or different from one another.  q represents an integer of 1 or greater, and Qq+,s each  independently represent a q-valent organic cation.]  [0005]  In the related art, a photosensitive resin composi› tion that contains a polyfunctional epoxy resin, a cationic  polymerization initiator, a solvent, and a surfactant is dis› closed as a photosensitive material forming the photosensi› tive resin film (see PTL 1).  [0004]  Further, a photosensitive resin composition is used  for a spacer between a semiconductor wafer and a transpar› ent substrate. For example, a spacer is obtained, using a  negative photosensitive resin composition, by forming a  photosensitive resin film on a surface of a semiconductor  wafer or the like, performing selective exposure on the  photosensitive resin film to radiation such as light or elec› tronic beams, performing a development treatment to form  a pattern, and pressure-bonding the pattern to a transparent  substrate (for example, a glass substrate). In this photosen› sitive resin composition, it is necessary to perform pattern› ing in an excellent shape without residues during the devel› opment treatment according to a photolithography method.  [0003]  In recent years, with miniaturization and densifi› cation of electronic components, there has been an increas› ing demand for a photosensitive resin composition used for  an electronic component having a hollow sealing structure,  such as a surface acoustic wave (SAW) filter. In formation  of the hollow sealing structure of such an electronic com› ponent, it is necessary to reduce the thickness of a cured film  formed by curing a photosensitive resin composition and to  strengthen the cured film.  [0009]  According to a first aspect of the present invention,  there is provided a negative type photosensitive resin com› position containing: an epoxy group-containing resin (A); a  metal oxide (M); and a cationic polymerization initiator (I),  the cationic polymerization initiator (I) containing one or  more selected from the group consisting of a compound  represented by Formula (Il) and a compound represented by  Formula (I2).  (11)  (12)  [0008]  The present invention has been made in consider› ation of the above-described problems, and an object thereof  is to provide a negative type photosensitive resin composi› tion from which a cured film having improved hardness can  be obtained and a pattern having an excellent shape can be  formed; a photosensitive resist film which has a photosen› sitive resin film formed by using the negative type photo› sensitive resin composition; a pattern forming method; a  cured film; and a method of producing the cured film.  [0001]  The present invention relates to a negative type  photosensitive resin composition, a photosensitive resist  film having a photosensitive resin film formed by using the  negative type photosensitive resin composition, a pattern  forming method, a cured film, and a method of producing the  cured film.  [0002]  Priority is claimed on Japanese Patent Application  No. 2016-170206, filed on Aug. 31, 2016, the content of  which is incorporated herein by reference. 