JPH0223782A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To remove the loss of a picture element at a connection part between elements in a solid-state image pickup device in which the number of the picture elements is increased by combining plural pieces of solid-state image pickup elements by arranging the solid-state image pickup elements so that surfaces formed by their photoelectric converting parts face each other. CONSTITUTION:Infrared rays made incident from the back of the solid-state image pickup element 1 is detected by the photoelectric converting array 4 of the element 1 after passing through the element 1. Besides, the infrared rays made incident to an area other than the array 4 is transmitted through the substrate of the element 1 as it is, and reaches the photoelectric converting arrays 5, 6 of the solid-state image pickup elements 2, 3, and is detected. Here, supposing the pitch of the picture element of the elements 1 to 3 is d0, if the elements 1 to 3 are arranged so that distance (d) between the centers of the picture elements at the ends of the arrays 4 and 5 comes equal to d0, the photoelectric converting arrays of the elements 1 and 3 is connected continuously. Therefore, an image can be picked up by the area of large area formed by the arrays 4 and 5, and a picture free from the loss of the picture at the connection part between the elements can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a solid-state imaging device, and particularly to the configuration of an infrared imaging device.

[Conventional technology]

Solid-state imaging devices in which a photoelectric conversion element array and a mechanism for reading electrical signals are integrated on the same semiconductor substrate are already used in video cameras and the like in the visible region. On the other hand, the development of solid-state imaging devices in the infrared region is also progressing, and in particular, infrared solid-state imaging devices that use silicon Schottky barrier diodes as photoelectric conversion parts have been developed that have the same resolution as visible solid-state imaging devices.

Recently, there has been a demand for solid-state imaging devices with even better resolution. Solid-state imaging devices in the visible range can meet this demand by further miniaturizing pixels, but solid-state imaging devices in the infrared region have long wavelengths of infrared light, so considering the diffraction limit, it is difficult to miniaturize pixels. There is a limit. Therefore, in an infrared solid-state imaging device, increasing the number of pixels results in an increase in the area of the device, resulting in a decrease in yield due to an increase in chimney size. Furthermore, when a pattern is formed using a reduction projection type exposure device, there is a limit to the area that can be transferred, so the chip size cannot be increased. Therefore, a method shown in FIG. 4 can be considered as a method of increasing the resolution of an infrared solid-state image sensor.

In FIG. 4, 11, 12, 13 are the 1st. 2nd, 3rd
The solid-state image sensors 14, 15, and 16 are the first solid-state image sensors, respectively. Second. This is a photoelectric conversion section of a third solid-state image sensor arranged in an array. The solid-state imaging devices 11, 12, and 13 are arranged side by side so that the gaps between the devices are extremely small. Therefore, the solid-state imaging device composed of elements 11, 12, and 13 is
Effectively, it has three photoelectric conversion arrays (14, 15, and 16), and the imaging area is tripled compared to the case where it is configured with only one solid-state image sensor, and in turn, it can have three times the resolution. can.

[Problem to be solved by the invention]

Conventional solid-state imaging devices are configured as described above.
Since light cannot be detected in the gaps between the elements, there is a problem in that pixels are lost at the junctions between the elements.

This invention was made to solve the problems of the conventional devices as described above.In a solid-state imaging device in which the number of pixels is increased by combining a plurality of solid-state imaging devices, the connection between each element is The purpose of this invention is to obtain a solid-state imaging device that eliminates pixel defects.

[Means to solve the problem]

The solid-state imaging device according to the present invention has one or more solid-state imaging devices on an area other than the photoelectric conversion array portion of the solid-state imaging device serving as a substrate, with their photoelectric conversion portion forming surfaces facing each other and each other. The areas where the photoelectric conversion units are arranged are arranged so that they partially overlap or do not overlap.

[Effect]

In this invention, since the solid-state image sensors are arranged as described above, it is possible to arrange the elements so that the connecting parts of the elements in the photoelectric conversion array part of each solid-state image sensor are connected continuously. When increasing the number of pixels by combining multiple solid-state image sensors, it is possible to eliminate image loss at the connection between the elements.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a solid-state imaging device according to an embodiment of the present invention. FIG. 2 is a plan view thereof. In the figure,
1 is a solid-state image sensor serving as a substrate, 2.3 is a solid-state image sensor,
4, 5.6 are photoelectric conversion array sections of the solid-state image sensors 1, 2.3, respectively.

Elements 2 and 3 are arranged so that their photoelectric conversion part forming surfaces face the photoelectric conversion part forming surface of element 1, and infrared light enters from the back surface of element 1.

Photoelectric conversion array sections 5 and 6 of elements 2 and 3 are shown in FIG.

As shown in FIG. 2, the elements 1 are arranged so that the distance between the centers of the end pixels is d at the position in contact with the photoelectric conversion array section 4. The solid-state image sensor 1.23 is an infrared solid-state image sensor in which an infrared detector array 4, 5.6 of Schottky barrier diodes and means for reading out optical signals thereof are monolithically formed on a Si semiconductor, for example.

The infrared solid-state imaging devices 1, 2, and 3 have their detector forming surfaces facing each other. As a mounting method for realizing such a configuration, the infrared solid-state imaging devices 1 and 2.3 may be bonded together with an adhesive or the like, or may be bonded together using a bump as shown in FIG. In this figure 3, 6
is I10 pad of chip 1, 7.8 is chip 2 or 3
The pad 9 formed on the top is an In bump that connects the pads 6 and 7 and fixes the chips 1 and 3.

Pad 7.8 is chip 1! It becomes 10 bad.

Further, 10 is the I10 pad of chip 2 or 3.

Next, the operation will be explained. Since the St semiconductor is transparent to infrared light, the direction of light incidence may be either the detector forming surface or the back surface thereof. Infrared light incident from the back surface of the element 1 passes through the element 1 and is detected by the photoelectric conversion array 4 of the element 1. Further, infrared light incident on a region other than the photoelectric conversion array 4 passes through the substrate of the element 1 as it is, reaches the photoelectric conversion arrays 5 and 6 of the elements 2 and 3, and is detected. Furthermore, the pixel pitch of the solid-state image sensors 1, 2, and 3 is d. Then, the distance d between the centers of the pixels at the ends of the photoelectric conversion arrays 4 and 5 is do
If elements 1, 2.3 are arranged so that they are equal to , then elements 1 and 2. The photoelectric conversion arrays of elements 1 and 3 are connected in series. Therefore, an image can be captured in a large area formed by the photoelectric conversion arrays 4, 5, and 6, and an image can be obtained without any image defects at the joints between the elements.

As described above, according to this embodiment, one or more solid-state image sensors are placed on an area other than the photoelectric conversion array section of a solid-state image sensor serving as a substrate so that their pixel forming surfaces face each other. Because of this arrangement, it is possible to ensure that the pixel connections between each element are connected continuously, and it is possible to eliminate image loss at the pixel connection areas when increasing the number of elements to improve resolution. .

In the above embodiment, the photoelectric conversion arrays 4, 5゜6 do not overlap and are arranged so that the distance between the pixels at the end of each element is the same as the pixel pitch, but this distance is determined by the pixel pinch. The pixels may be different from each other, or some edge pixels may overlap.

Further, although the above embodiment shows an arrangement including three solid-state image sensors, the number may be two or three or more, and the arrangement is not limited to the above embodiment.

Furthermore, although the above embodiments show the case where the substrate is a Si semiconductor, it is also possible to use other semiconductors such as HgCdTe or InSb.
However, the same effect as in the above embodiment can be obtained.

〔Effect of the invention〕

As described above, according to the solid-state imaging device according to the present invention,
One or more solid-state image sensors are arranged on an area other than the photoelectric conversion array section of the first solid-state image sensor so that their pixel formation surfaces face each other, so that the pixels between each element are connected. It becomes possible to make the parts connected continuously, and it becomes possible to eliminate image loss at the part where the elements connect when increasing the number of elements and improving the resolution.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a solid-state imaging device according to an embodiment of the present invention, FIG. 2 is a plan view of the device shown in FIG. 1, and FIG. 3 is a diagram showing an example of a mounting method for realizing the configuration of FIG. 1. , FIG. 4 is a plan view of a conventional solid-state imaging device. In the figure, 1 and 2.3 are solid-state image sensors, and 45.6 is a photoelectric conversion array.

Claims (1)

[Claims] (1) In a solid-state imaging device, a plurality of solid-state imaging devices are arranged one-dimensionally or two-dimensionally on a semiconductor substrate and have a photoelectric conversion section sensitive to infrared rays and a mechanism for reading out electrical signals from the photoelectric conversion section. The remaining solid-state image sensors are placed on top of the first solid-state image sensor of the plurality of solid-state image sensors so that the photoelectric conversion portion forming surfaces of the first solid-state image sensor and the remaining solid-state image sensors face each other. The solid-state imaging device is arranged such that the photoelectric conversion sections of the first solid-state imaging device and the remaining solid-state imaging devices partially overlap or do not overlap with each other. Device.