JP-7856424-B2 - Sealing sheets and electronic component devices
Inventors
- 清水 祐作
- 土生 剛志
- ▲浜▼名 大樹
Assignees
- 日東電工株式会社
Dates
- Publication Date
- 20260511
- Application Date
- 20211224
Claims (4)
- This is a sealing sheet containing epoxy resin, phenolic resin, urea-based curing accelerator, inorganic filler, and thermoplastic resin. In the epoxy resin, phenolic resin, thermoplastic resin, and urea-based curing accelerator, the proportion of the epoxy resin is 50% by mass or less. The percentage change (A0-A1) from the adhesive strength A0 of the sealing sheet immediately after manufacturing to the adhesive strength A1 of the sealing sheet after 24 hours at 23°C and 50% RH ([A0-A1]/A0×100) is 10% or less. An sealing sheet in which the ratio of the amount of heat generated by differential scanning calorimetry of the sealing sheet after heating it at 150°C for 20 minutes to the amount of heat generated by differential scanning calorimetry of the sealing sheet immediately after manufacture is 0.10 or less.
- The encapsulating sheet according to claim 1, wherein the urea-based curing accelerator is an aliphatic urea compound.
- The sealing sheet according to claim 1 or claim 2, wherein the percentage of variation (L1-L2) from the first entry length L1 to the second entry length L2 determined by test Y, at the first entry length L1 determined by test X, is 90% or less ([L1-L2]/L1×100). <Exam X> Follow the steps below from 1 to 5 in order. Step 1: Prepare a sample with a thickness of 200 μm from the sealing sheet immediately after manufacturing. Separately, prepare a mounting substrate comprising a glass substrate and nine dummy chips, each measuring 1 mm × 1 mm × 200 μm thick and arranged in a line with a spacing of 300 μm between them, which are mounted on the upper surface of the glass substrate via bumps. Step 2: Using a vacuum plate press, the sample is pressed toward the glass substrate at a temperature of 65°C, a vacuum of 1.6 kPa or less, a pressing pressure of 0.2 MPa, and for 60 seconds. Step 3: The sample is brought into contact with the upper surface of the dummy chip and left for 30 minutes at 23°C and 50% RH. Step 4: The sample is heat-cured by heating it at 150°C for 1 hour under atmospheric pressure. Step 5: Measure the length L1 of the sample entering the gap between the lower surface of the dummy chip located in the center and the upper surface of the glass substrate. <Test Y> Steps 1 through 5 described above are carried out. However, the waiting time in step 3 is changed from 30 minutes to 24 hours . In step 5 , the second entry length L2 of the sample is measured.
- A sealing sheet molded from a sealing sheet according to any one of claims 1 to 3, An electronic element device comprising an electronic element sealed by the aforementioned sealing sheet.
Description
This invention relates to a sealing sheet and an electronic device. It is known that electronic devices are manufactured by encapsulating electronic elements using encapsulation sheets (see, for example, Patent Document 1 below). The sealing sheet described in Patent Document 1 contains epoxy resin, phenolic resin (curing agent), and imidazole-based curing accelerator. The sealing sheet forms a sealant by thermal curing after embedding electronic elements. Japanese Patent Publication No. 2017-92103 Figure 1A shows the first step of both Test X and Test Y. Figure 1B shows the second through fifth steps of both Test X and Test Y.This is a cross-sectional view of an electronic device. 1. Sealing Sheet An embodiment of the sealing sheet of the present invention will be described. Encapsulation sheets are used to encase electronic components. Encapsulation sheets have thickness. They extend in a planar direction. The planar direction is perpendicular to the thickness direction. Encapsulation sheets have a roughly plate-like (film-like) shape. 1.1 Components of the sealing sheet The sealing sheet contains epoxy resin, phenolic resin, urea-based curing accelerator, and inorganic filler. Specifically, the sealing sheet is formed in sheet form from a thermosetting composition containing the above components. The thermosetting composition also contains a resin component and a filler component. The blending ratio of the resin component in the thermosetting composition is, for example, 1% by mass or more, preferably 5% by mass or more, and also, for example, 25% by mass or more, preferably 15% by mass or less. The blending ratio of the filler component in the thermosetting composition is, for example, 75% by mass or more, preferably 85% by mass or more, and also, for example, 99% by mass or more, preferably 90% by mass or less. The blending ratio of the filler component to 100 parts by mass of the resin component is, for example, 300 parts by mass or more, preferably 700 parts by mass or more, and also, for example, 3000 parts by mass or less, preferably 1500 parts by mass or less. The resin component contains the epoxy resin, phenolic resin, and urea-based curing accelerator mentioned above. The filler component contains an inorganic filler. 1.1.1 Epoxy Resins Epoxy resins are the main component in thermosetting compositions. The type of epoxy resin is not limited. Examples of epoxy resins include difunctional epoxy resins and polyfunctional epoxy resins with three or more functions. Examples of difunctional epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, modified bisphenol A type epoxy resins, modified bisphenol F type epoxy resins, and biphenyl type epoxy resins. Examples of polyfunctional epoxy resins include phenol novolac type epoxy resins, cresol novolac type epoxy resins, trishydroxyphenylmethane type epoxy resins, tetraphenyloleethane type epoxy resins, and dicyclopentadiene type epoxy resins. Epoxy resins can be used alone or in combination of two or more types. Preferably, the epoxy resin is a difunctional epoxy resin, and more preferably, bisphenol F type epoxy resin and modified bisphenol A type epoxy resin. Bisphenol F type epoxy resin is preferred from the viewpoint of suppressing the percentage variation in adhesive strength (described later) and reducing the percentage variation in penetration length (described later). On the other hand, modified bisphenol A type epoxy resin is preferred from the viewpoint of reducing the ratio related to heat generation (described later). The proportion of epoxy resin in the sealing sheet is not limited. For example, the proportion of epoxy resin in the sealing sheet is 1% by mass or more, preferably 2% by mass or more, and also, for example, 25% by mass or less, preferably 10% by mass or less. The proportion of epoxy resin in the resin component is, for example, 5% by mass or more, preferably 15% by mass or more, and also, for example, 50% by mass or less, preferably 25% by mass or less. 1.1.2 Phenolic Resin The phenolic resin is a latent phenolic resin that cures epoxy resins. The type of phenolic resin is not limited. Examples of phenolic resins include novolac-type phenolic resins and phenol-aralkyl resins. The phenolic resin can be used alone or in combination of two or more types. From the viewpoint of reducing the percentage of variation in adhesive strength (described later), phenol-aralkyl resin is preferred as the phenolic resin. Also, from the viewpoint of reducing the ratio related to DSC (described later), novolac-type phenolic resin is preferred as the phenolic resin. The blending ratio of phenolic resin to 100 parts by mass of epoxy resin is, for example, 10 parts by mass or more and 150 parts by mass or less. The blending ratio of phenolic resin in the sealing sheet is, for example, 0.5% by mass or more, preferably 2% by mass or more, and also, for example, 5% by mass or less, preferably 2.5% by mass or less. The blen