Solid-state image capturing apparatus, mounting method of solid-state image capturing apparatus, manufacturing method of solid-state image capturing apparatus, and electronic information device
A solid-state image capturing apparatus includes: an insulation substrate including an external lead terminal; a solid-state image capturing element fixed on the insulation substrate and including a microlens; and a transparent glass member positioned above the insulation substrate for sealing the solid-state image capturing element fixed on the insulation substrate, and an electrode of the solid-state image capturing element and the external lead terminal of the insulation substrate being connected by a wire, wherein the transparent glass member is positioned in such a manner that a hollow space is formed between a microlens of the solid-state image capturing element and the transparent glass member, and wherein portions of the insulation film, the solid-state image capturing element and the wire, which are exposed in the hollow space, are all covered with a protective film.
1. A solid-state image capturing apparatus, comprising:
an insulation substrate including an external lead terminal;
a solid-state image capturing element fixed on the insulation substrate and including a microlens; and
a transparent glass member positioned above the insulation substrate for sealing the solid-state image capturing element fixed on the insulation substrate, and
an electrode of the solid-state image capturing element and the external lead terminal of the insulation substrate being connected by a wire,
wherein the transparent glass member is positioned in such a manner that a hollow space is formed between a microlens of the solid-state image capturing element and the transparent glass member,
wherein portions of the insulation substrate, the solid-state image capturing element and the wire, which are exposed in the hollow space, are all covered with a protective film and
wherein a refractive index of the protective film is smaller than a refractive index of a constituent material of the microlens and larger than a refractive index of air.
2. A solid-state image capturing apparatus according to claim 1 , wherein the protective film is one of a SiO 2 film, a SiON film and a SiN film.
3. A solid-state image capturing apparatus according to claim 1 , wherein the protective film includes a multilayer structure where a plurality of transparent insulation films with different refractive indexes are laminated in such a manner that one with a smaller refractive index is positioned on a surface side.
4. A solid-state image capturing apparatus according to claim 3 ,
wherein the protective film includes a two layered structure where two transparent insulation films with different refractive indexes are laminated in such a manner that one with a smaller refractive index is positioned on a surface side, and
wherein the transparent insulation film constituting the protective film on an outer side is a SiO 2 film and the transparent insulation film constituting the protective film on an inner side is a SiN film.
5. A solid-state image capturing apparatus according to claim 3 ,
wherein the protective film includes a two layered structure where two transparent insulation films with different refractive indexes are laminated in such a manner that one with a smaller refractive index is positioned on a surface side, and
wherein the transparent insulation film constituting the protective film on an outer side is a SiON film and the transparent insulation film constituting the protective film on an inner side is a SiN film.
6. A solid-state image capturing apparatus according to claim 3 ,
wherein the protective film includes a two layered structure where two transparent insulation films with different refractive indexes are laminated in such a manner that one with a smaller refractive index is positioned on a surface side, and
wherein the transparent insulation film constituting the protective film on an outer side is a SiO 2 film and the transparent insulation film constituting the protective film on an inner side is a SiON film.
7. A solid-state image capturing apparatus according to claim 3 ,
wherein the protective film includes a three layered structure where three transparent insulation films with different refractive indexes are laminated in such a manner that one with a smaller refractive index is positioned on a surface side, and
wherein the transparent insulation film constituting the protective film on an outer side is a SiO 2 film, the transparent insulation film constituting the protective film on an inner side is a SiN film, and the transparent insulation film constituting the protective film in a middle portion is a SiON film.
8. A solid-state image capturing apparatus according to claim 1 , wherein the protective film has a refractive index that is successively changed to be smaller towards a surface side.
9. A solid-state image capturing apparatus according to claim 8 , wherein the protective film includes a SiON film in which a ratio of oxygen and nitrogen is successively changed in such a manner that the refractive index becomes smaller towards the surface side.
10. A solid-state image capturing apparatus according to claim 1 , wherein the protective film is formed by a plasma CVD method.
11. An electronic information device comprising an image capturing section for capturing an image of a subject, wherein the image capturing section is a solid-state image capturing apparatus according to claim 1 .
12. A mounting method of a solid-state image capturing apparatus, for mounting a solid-state image capturing element including a microlens on an insulation substrate including an external lead terminal, the method comprising:
a step of fixing the solid-state image capturing element on the insulation substrate;
a step of connecting an external lead terminal of the insulation substrate and an electrode of the solid-state image capturing element with a wire;
a step of forming a protective film on a surface of the insulation substrate in such a manner that exposed portions of the insulation substrate, the solid-state image capturing element and the wire are all covered with the protective film; and
a step of positioning a transparent glass member on the insulation substrate to seal the solid-state image capturing element in such a manner to form a hollow space between a microlens of the solid-state image capturing element and the transparent glass member
wherein the protective film is formed by a plasma CVD process prior to sealing the solid-state image capturing element with the transparent glass member.
13. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the step of forming the protective film, at least the solid-state image capturing element is housed in a jig that totally covers a side surface and a bottom surface of the solid-state image capturing element to perform the plasma CVD process.
14. A mounting method of a solid-state image capturing apparatus according to claim 13 , wherein the plasma CVD process is performed at least in two steps by changing an inclination of the jig so that a difference remains small between a thickness of the protective film formed on a surface side of the wire and a thickness of the protective film formed on a back side of the wire.
15. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the plasma CVD process, tetraethy orthosilicate or ethyl ethoxy silane and O 2 are used as a reaction gas, and a SiO 2 film is formed as the protective film.
16. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the plasma CVD process, SiH 4 , NH 3 and N 2 are used as a reaction gas, and a SiN film is formed as the protective film.
17. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the plasma CVD process, SiH 4 , N 2 O and He are used as a reaction gas, and a SiON film is formed as the protective film.
18. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the step of forming the protective film, the plasma CVD process is performed several times by changing a component of a reaction gas so that the protective film includes a multilayer structure that includes a plurality of transparent insulation films with different refractive indexes.
19. A mounting method of a solid-state image capturing apparatus according to claim 12 , wherein, in the step of forming the protective film, the plasma CVD process is performed by successively changing a component of a reaction gas so that a transparent insulation film with a successively changing refractive index is formed as the protective film.
20. A manufacturing method of a solid-state image capturing apparatus in which a solid-state image capturing element including a microlens is mounted on an insulation substrate including an external lead terminal and a transparent glass member is positioned above the insulation substrate so that the solid-state image capturing element fixed on the insulation substrate is sealed, the method comprising:
a step of fixing the solid-state image capturing element on the insulation substrate;
a step of connecting an external lead terminal of the insulation substrate and an electrode of the solid-state image capturing element with a wire;
a step of forming a protective film on a surface of the insulation substrate in such a manner that exposed portions of the insulation substrate, the solid-state image capturing element and the wire are all covered with the protective film;
wherein a refractive index of the protective film is smaller than a refractive index of a constituent material of the microlens and larger than a refractive index of air and
a step of positioning a transparent glass member on the insulation substrate to seal the solid-state image capturing element in such a manner to form a hollow space between a microlens of the solid-state image capturing element and the transparent glass member.