JPH04271154A - Manufacture of solid state image sensor - Google Patents

Abstract

PURPOSE:To accurately set a reference surface when a reins-molded solid state image sensor is mounted on a board. CONSTITUTION:A step 34 is formed at an outer frame 33 parallel to leads 32 of a lead frame, a sensor chip 10 is mounted at an island 31 of the outer frame, the leads 32 are bent perpendicularly, and contained in a recess 21 of a mold 20. Thermosetting transmission resin is filled in the recess 31, the resin is cured, a package is formed, the package is then removed from the mold 20, and the frame 33 of the lead frame and the leads 32 are cut in the same length. When this solid state image sensor is mounted on a board, the step 34 of the lead frame is used as a reference.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a resin mold type CC
The present invention relates to a method of manufacturing a solid-state image sensor such as a D-image sensor.

0002

2. Description of the Related Art The structure of a conventional solid-state image sensor using a ceramic package is shown in FIG. An internal lead 3a and an external lead 3b continuous with the internal lead 3a are embedded in the ceramic package 1 in advance, and a drive circuit for driving an image sensor and the like is connected to the external lead 3b exposed to the outside. Further, a recess is formed in the ceramic package 1, and a sensor chip 2 having a photoelectric conversion element formed on one side is housed in the recess. Then, the electrode pads of the sensor chip 2 are connected to the tips of the internal leads 3a exposed in the recesses by wire bonding. Furthermore, sensor chip 2
The recessed portion in which the is housed is sealed by attaching the glass plate 4.

However, in the solid-state imaging device as described above, when the sensor chip 2 is bonded into the recess of the ceramic package 1, and then the sensor chip 2 and the internal leads 3a are wire-bonded to perform color imaging, it is difficult to perform color imaging. In addition, many assembly steps such as attaching color filters are required, which increases the cost and increases the frequency of dust adhering to the light-receiving surface of the sensor chip 2 during the assembly process. Furthermore, since the ceramic package 1 itself is expensive, a decrease in yield during the assembly process is one of the major factors in increasing costs.

[0004] Therefore, molding the sensor chip with a translucent resin has been proposed, for example, in Japanese Unexamined Utility Model Publication No. 1-113347. If the sensor chip is molded using such a light-transmitting resin, the assembly process will be simpler than when using the ceramic package 1, and an inexpensive solid-state imaging device can be provided. Furthermore, the present applicant has also proposed in Japanese Patent Application No. 2-111923 that an imaging device be formed by molding a sensor chip with a light-transmitting resin.

FIG. 7 shows a method of forming a sensor chip package using a light-transmitting resin. The lead frame includes an island portion 11 to which the sensor chip 10 is die-bonded, and lead portions 1 arranged around the island portion 11.
The sensor chip 10 is attached to the island part 11, the pad part of the sensor chip 10 and the tip of the lead part 12 are wire-bonded, and the lead part 12 is attached to the island part 11. 11
After being bent perpendicularly to the recess 2 of the mold 20
It is stored in 1. The recess 21 of the mold 20 is formed according to the shape of the image sensor to be obtained, and is provided with a stepped portion 22 that supports the lead frame 11 and a positioning pin 23 that fixes the position of the lead frame. Therefore, the position of the sensor chip 10 relative to the bottom surface of the recess 21 of the mold 20 is determined by the stepped portion 22, and the position of the sensor chip 10 relative to the side surface is determined by the positioning pin 23.

The lead frame with the sensor chip 10 attached to the island portion 11 is housed in the recess 21 with the side on which the sensor chip 10 is attached facing the bottom of the recess 21, and is made of a thermosetting transparent resin. It is molded by. This light-transmitting resin is filled into the recess 21 after the lead frame is housed in the recess 21, and is cured by heating to form a package. When heat-curing a translucent resin in this way, the air bubbles contained within the translucent resin are expelled from the resin during curing, which eliminates the generation of air bubbles within the translucent resin. . Then, the formed package is taken out from the mold 20 and the outer frame 13
By cutting the lead portion 12, a solid-state imaging device is obtained as shown in FIG. In this solid-state image sensor, the back surface of the light-transmitting resin is not flat, making it impossible to obtain an accurate reference surface when attaching the image sensor to the substrate.
Leaving a part of 3 for a determined length, the remaining outer frame 13
The reference surface is obtained from the tip of a.

[0007]

[Problem to be Solved by the Invention] However, since the outer frame 13a left on the package side is shorter than the lead part 12, a step is created between the part where the outer frame 13 is cut and the part where the lead part 12 is cut. , once the lead part 12
After cutting the outer frame 13b to a predetermined length, it becomes necessary to perform a cutting process twice to cut off the excess outer frame 13b. Also,
Although it is not impossible to cut the lead part 12 and the outer frame 13 at the same time by using a cutting jig, it is not possible to cut the lead part 12 and the outer frame 13 at the same time. However, since the setting of conditions becomes complicated, it is not necessarily more effective than performing the cutting process twice. Therefore, problems such as a decrease in yield due to an increase in the number of manufacturing steps and an increase in manufacturing costs arise.

[0008] Therefore, the present invention aims to improve the lead portion 12 of a lead frame in the production of a resin molded solid-state image sensor.
Another object of the present invention is to simplify the process of cutting the outer frame 13, and to provide an inexpensive and highly reliable solid-state imaging device.

[0009]

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and is characterized by a semiconductor chip having a plurality of photoelectric conversion elements arranged in a matrix. Attaching the lead frame to the island portion of the lead frame and bending the lead portion of the lead frame substantially perpendicularly to the semiconductor chip; storing the lead frame with the semiconductor chip attached thereto in a recess forming a package shape; A step of filling the inside of the recess with a thermosetting translucent resin and then curing the translucent resin by heating, and extending the lead portion of the lead frame exposed from the cured translucent resin to a predetermined length. In the method for manufacturing a solid-state imaging device, the method includes a step of cutting the solid-state imaging device with a portion remaining, the outer frame supporting the island portion and the lead portion of the lead frame being exposed from the portion embedded in the translucent resin. A wide portion wider than the lead portion is provided over a part of the portion, and the end portions of the wide portion on the side exposed from the translucent resin are set at equal distances from the island portion.

0010

[Operation] According to the present invention, when a solid-state image sensor is mounted on a substrate from the end of the wide part of the outer frame of the lead frame exposed from the package, that is, from the step at the narrow part of the outer frame, Since it is possible to obtain a reference surface of 1, it is not necessary to make the outer frame portion shorter than the lead portion, and the outer frame portion and the lead portion can be easily cut at the same time in one process.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described with reference to the drawings. A method for manufacturing a solid-state image sensor according to the present invention is shown in FIG. In this figure, the mold 20 is the same as in FIG. 6, and the same parts are given the same reference numerals. The lead frame with the sensor chip 10 attached to the island portion 31 is attached to the sensor chip 1 after the lead portion 32 is bent, as in the case of FIG.
It is stored in the recess 21 of the mold 20 with the 0 side facing the bottom. As shown in FIG. 3, this lead frame includes an island portion 31 on which the sensor chip 10 is attached, a lead portion 32 arranged to surround this island portion 31, and an outer surface supporting the island portion 31 and the lead portions 32. It consists of a frame 33, and the width of this outer frame 33 is equal to the width of the island portion 31.
A step 34 is formed in a middle portion of the outer frame 33 parallel to the lead portion 32 and is widened from both sides of the lead portion 32 to the leading end thereof. The steps 34 are provided at equal distances from the center of the outer frame 33 because they are used to obtain a reference surface when mounting the solid-state image sensor on the substrate. Further, at both ends of the island portion 31, there are positioning holes 35 that are connected to the positioning pins 42 in the recessed portion 21.
is provided.

After the lead frame is housed in a predetermined position within the recess 21, a thermosetting translucent resin is filled in the recess 21, and this translucent resin is heated together with the lead frame. The transparent resin is cured to form a package. After this package is formed as shown in FIG. 2, the light-transmitting resin package is taken out from the mold 20, and the lead portion 32 and outer frame 33 are cut to obtain a solid-state imaging device. At this time, the length of the outer frame 33a left on the package side is equal to the length of the lead part 32, and the length of the unnecessary outer frame 33a is equal to the length of the lead part 32.
By cutting 3b once, the lead portion 32 and the outer frame 33a are separated.
The length of is set. In such a solid-state image sensor, when the outer frame 33 is inserted into a hole provided in the substrate, it will stop at the step 34, so depending on the position of the step 34 of the outer frame 33, the solid-state image sensor relative to the substrate, Specifically, the position of the sensor chip 10 will be determined.

According to the above structure, it is not necessary to provide a step between the lead portions 32 and the outer frame 33 exposed from the package, so that the lead portions 32 and the outer frame 33 can be cut to the same length at the same time. Therefore, the lead frame cutting process can be simplified and manufacturing costs can be reduced. Next, another embodiment is shown in FIG. The lead frame used here is provided so that the width of the outer frame 43 becomes gradually thinner, and a step-like step 45 is provided. By gradually reducing the width of the outer frame 43a exposed from the package, the height of the solid-state image sensor can be selected by changing the size of the hole in the substrate for mounting the solid-state image sensor. Can be done.

In addition to the outer frame 43, the width of the lead portion 42 is gradually narrowed to provide a step 44 on the lead portion 42, so that the reference surface for mounting on the board can be obtained by the lead portion 42 itself. is also possible. In this case, since the distance between the solid-state image sensor and the substrate can be set by the size of the hole provided in the substrate, it is possible to change the distance between the solid-state image sensor and the substrate at the stage of assembling the device.

[0015]

According to the present invention, by simplifying the manufacturing process, it is possible to prevent a decrease in manufacturing yield and reduce manufacturing costs, and it is possible to obtain an inexpensive and highly reliable solid-state imaging device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view illustrating an embodiment of the present invention.

FIG. 2 is a side view of a solid-state imaging device obtained by the manufacturing method of FIG. 1;

FIG. 3 is a plan view of a lead frame used in the manufacturing method of the present invention.

FIG. 4 is a side view illustrating another embodiment of the present invention.

FIG. 5 is a perspective view showing the structure of a conventional solid-state image sensor.

FIG. 6 is a cross-sectional view illustrating a method of manufacturing a solid-state image sensor.

7 is a side view of a solid-state imaging device obtained by the manufacturing method of FIG. 6. FIG.

[Explanation of symbols]

1 Ceramic package 2, 10 Sensor chip 3a External lead 3b Internal lead 4 Glass plate 11, 31, 41 Island part 12, 32, 42 Lead part 13, 33, 43 Outer frame 34, 44, 45 steps 20 Mold 21 Recess 22 Step part 23 Positioning pin

Claims (3)

[Claims] 1. Mounting a semiconductor chip having a plurality of photoelectric conversion elements arranged in a matrix on an island portion of a lead frame, and bending the lead portion of the lead frame substantially perpendicularly to the semiconductor chip;
accommodating the lead frame with the semiconductor chip mounted in a recess forming a package shape, filling the recess with a thermosetting translucent resin, and then heating to cure the translucent resin; A method for manufacturing a solid-state imaging device, comprising: cutting the lead portion of the lead frame exposed from the cured light-transmitting resin, leaving a predetermined length. The outer frame that supports the part is provided with a wide part that is wider than the lead part from the part embedded in the translucent resin to a part of the exposed part, and the outer frame supports the lead part on the side exposed from the translucent resin. A method for manufacturing a solid-state image sensor, characterized in that the ends of the wide portions are set at equal distances from the island portion. 2. The outer frame portion of the lead frame is a portion parallel to the lead portion and has the same width as the lead portion except for the wide portion, and the outer frame portion and the lead portion are connected to each other. 2. The method of manufacturing a solid-state image sensor according to claim 1, wherein the solid-state image sensing device is cut while leaving the same length. 3. The solid-state imaging device according to claim 1, wherein the width of the outer frame portion or the lead portion of the lead frame exposed from the light-transmitting resin is gradually narrowed toward the tip end. Production method.