Mold release film and method of process for producing a semiconductor device using the same
View Patent ↗A mold release film, which is adapted to be disposed on the cavity surface of a mold to form a resin-encapsulated portion by encapsulating a semiconductor element of a semiconductor device with a curable encapsulation resin, has a tensile modulus of elasticity of from 10 to 24 MPa at 132° C. as measured in accordance with JIS K 7127, and a peak peel resistance of at most 0.8 N/25 mm.
1. A mold release film adapted to be disposed on the cavity surface of a mold to form a resin-encapsulated portion by encapsulating a semiconductor element of a semiconductor device with a curable encapsulation resin,
the mold release film having:
a tensile modulus of elasticity of from 10 to 24 MPa at 132° C. as measured in accordance with JIS K 7127, and
a peak peel resistance of at most 0.8 N/25 mm.
2. The mold release film according to claim 1 , which is a film made of a fluororesin.
3. The mold release film according to claim 2 , wherein the fluororesin is a copolymer including units derived from tetrafluoroethylene, units derived from ethylene and units derived from a third monomer other than them.
4. The mold release film according to claim 3 , wherein the third monomer is (perfluorobutyl)ethylene.
5. The mold release film according to claim 4 , wherein the copolymer is a copolymer which has a molecular ratio of from 80/20 to 40/60 of repeating units derived from tetrafluoroethylene to repeating units derived from ethylene (tetrafluoroethylene/ethylene) and,
wherein the molecular ratio of repeating units derived from (perfluorobutyl)ethylene to all repeating units (100 mol %) is from 5 to 10 mol %.
6. A process for producing a semiconductor device by encapsulating a semiconductor element with a curable encapsulation resin by means of a mold; comprising disposing a mold release film on a cavity surface of the mold in contact with the encapsulation resin, the mold release film having a tensile modulus of elasticity of from 10 to 24 MPa at 132° C. as measured in accordance with JIS K 7127, and a peak peel resistance of at most 0.8 N/25 mm, and form a resin-encapsulated portion by curing the encapsulation resin in such a state that the encapsulation resin is brought into contact with the mold release film.
7. The process for producing a semiconductor device according to claim 6 , wherein the semiconductor device is a light emitting diode, the semiconductor element is a light emitting element, and the resin-encapsulated portion is a lens portion.
8. The process for producing a semiconductor device according to claim 7 , wherein the lens portion has an externally exposed portion, the externally exposed portion having an area of at least 56 mm 2 .
9. The process for producing a semiconductor device according to claim 6 , wherein the encapsulation resin is a thermosetting resin, and the encapsulation resin is thermally cured in such a state that the encapsulation resin is brought into contact with the mold release film.
10. The process for producing a semiconductor device according to claim 6 , wherein the formation of the resin-encapsulated portion by means of a mold is carried out by a compression molding method.
11. The process for producing a semiconductor device according to claim 6 , wherein the formation of the resin-encapsulated portion by means of a mold is carried out by a transfer molding method.
12. A process for producing a semiconductor device, including the following steps (α1) to (α5):
(α1) a step of disposing the mold release film as defined in claim 1 to cover a mold cavity,
(α2) a step of vacuum-suctioning the mold release film to a mold cavity surface side,
(α3) a step of packing an encapsulation resin in the cavity,
(α4) a step of obtaining a semiconductor device by disposing a semiconductor element at a certain position in the cavity, and encapsulating the semiconductor element with the encapsulation resin to form a resin-encapsulated portion, and
(α5) a step of taking out the semiconductor device from the mold.
13. A process for producing a semiconductor device, including the following steps (β1) to (β5):
(β1) a step of disposing the mold release film as defined in claim 1 to cover a mold cavity,
(β2) a step of vacuum-suctioning the mold release film to a mold cavity surface side,
(β3) a step of disposing a semiconductor element at a certain position in the cavity,
(β4) a step of obtaining a semiconductor device by packing an encapsulation resin in the cavity, and encapsulating the semiconductor element with the encapsulation resin to form a resin-encapsulated portion, and
(β5) a step of taking out the semiconductor device from the mold.
14. A process for producing a semiconductor device according to claim 12 , wherein the semiconductor device is a light emitting diode,
the semiconductor element is a light emitting element,
the resin-encapsulated portion is a lens portion, and
the lens portion has an externally exposed portion, the externally exposed portion having an area of at least 56 mm 2 .
15. A process for producing a semiconductor device according to claim 13 , wherein the semiconductor device is a light emitting diode,
the semiconductor element is a light emitting element,
the resin-encapsulated portion is a lens portion, and
the lens portion has an externally exposed portion, the externally exposed portion having an area of at least 56 mm 2 .