Optical sensor device

Abstract

A package for an optical sensor device has a double molding structure in which a first resin molded portion (1) and a second resin molded portion (2) are subjected to contact fitting. The first resin molded portion (1) has a structure in which peripheries of a die pad portion (8) on which an optical sensor element (5) is mounted and a part of leads (3a, 3b) are molded with a resin so as to be integrated. The second resin molded portion (2) has a structure in which the periphery of the first resin molded portion (1) is molded with a resin so as to form an outer shape. When a cavity is formed, a glass substrate (4) having a filter function and an upper surface of the resin molded portions are bonded to each other to form a cavity structure.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an optical sensor device. More specifically, the present invention relates to a package structure of the optical sensor device.[0003]2. Description of the Related Art[0004]FIG. 11 is a sectional view illustrating an example of a related-art package (FIG. 2 of Japanese Patent Application Laid-open No. 2002-198455). This package has the following structure. A package body 21 includes a lead 25 and a cavity formed by a bottomed portion 23 and an inner side surface 24 that are made of a resin material. A semiconductor element 22 is mounted on the bottomed portion 23 of the package body 21, and a lid 27 is provided on a package upper surface. A surface of a part of the lead 25 is exposed from the bottomed portion 23, and another part of the lead 25 is exposed to outside through the package formed of a resin molded portion so as to be used as an external terminal. An electrode is formed on a s...

AI Technical Summary

Benefits of technology

[0016]The optical sensor device according to one embodiment of the present invention can have a hollow structure in which the optical sensor element is sealed. In addition, the peripheries of the lead having the wire bonding portion exposed and the die pad are subjected to contact fitting molding with the first resin molded portion integrated by resin molding, and the periphery of the first resin molded portion, in which the wire bonding portion and the die pad surface are arranged on the bottomed portion, is subjected to contact fitting molding with the second resin molded portion so as to form the integrated package structure having the cavity. Thus, in a structure in which the periphery of the optical sensor element is molded with a resin, stress applied to the optical sensor element is removed. Moreover, the interface between the die pad and lead and the resin is allowed to have high adhesion and high airtightness, and contact fitting with a strong holding force of the lead can be achieved.

[0017]Further, the lead is bent and cut so as to also serve as the external lead terminal. The first resin molded portion and the second resin molded portion hold the lead. Therefore, at least mechanical stress applied to the lead can be received and alleviated by the second resin molded portion. In addition, the lead held even by the first resin molded portion is less liable to receive stress, and water and the like can be prevented from entering the package. Therefore, even in a package having a risk in that the factor for degrading reliability may be increased due to the increase in number of lead terminals, based on the fact that the mechanical stress and the entrance path of the water and the like increase in proportional to the number of the external lead terminals, an optical sensor device excellent in stability of characteristics and reliability can be provided.

Problems solved by technology

In this structure, there are the following problems: the removal preventing force of the lead is low; the holding area thereof is small; and the lead surface made of a metal has low adhesion to the resin.

Further, in the case where the part of the lead 25 serving as the external lead terminal is bent and cut, mechanical stress is concentrated on a root portion between the molding resin and the lead 25 exposed to outside from the molding resin, so that the resin is liable to be peeled and cracked.

Further, a gap remains at an interface between the lead 25 and the resin, with the result that the package has low airtightness.

Therefore, it is difficult to obtain a strong holding force of the lead 25.

Further, there is also a problem in that water is liable to enter the package from outside, and in addition, ambient environment may change.

Thus, it becomes more difficult to obtain high reliability.

However, even in the structure in which the periphery of the lead 25 is sealed with the transparent mold resin 28 formed of an epoxy resin, the adhesion between the metal and the resin is not sufficient, and there is a significant difference in expansion coefficient between the metal and the resin.

In addition, there is a risk in that an external appearance of the package may be impaired.

Images