JPH06236985A - Solid-state image pick-up device - Google Patents

Abstract

PURPOSE:To realize a CCD solid-state image pick-up element able to make a CCD solid-state image pick-up device and a high breakdown strength driving IC one chip without lowering a characteristic of a CD solid pick-up element. CONSTITUTION:The mutually electrically separated first p-type insular region 2 and second p-type insular region 3 are formed on an n-type substrate 1. An n-type insular region 4 is formed in the second p-type insular region 3 by high energy ion implantation. A photodetector part 5, a vertical transfer CCD 6, a horizontal transfer CCD 7 and a charge detection part 8 are formed in the first p-type insular region 2. A drive circuit 9 driving the vertical transfer CCD 6 and the horizontal transfer CCD 7 are constituted of a MOSFET formed on the second p-type insular region 3 and the n-type insular region 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device which can be used in an image pickup section of a video camera.

[0002]

2. Description of the Related Art CC used in an image pickup section of a video camera
As a driving means of the D solid-state image pickup device, a 5V logic level is + 15V, 0 for driving a vertical transfer CCD.
It is necessary to have a high withstand voltage drive IC that converts the level into three values of V and -10V.

In a CCD solid-state image pickup device, a light receiving portion, a charge transfer portion and a charge detecting portion are formed in a p-type island region formed on an n-type substrate, and the n-type substrate is usually +.
The p-type island region is biased to 5V to + 10V and 0V.

On the other hand, the high withstand voltage drive IC is composed of a CMOSFET formed on an n-type or p-type substrate, but the substrate voltage is +15 V or more on the n-type or p-type substrate due to the device configuration. -10V is biased.

[0005]

The video camera is aimed at ultra-compactness and ultra-lightness, and it is desired to provide a CCD solid-state image pickup device and a high-voltage drive IC on one chip. In the configuration of the device, there is a problem that the substrate voltage of the CCD solid-state image pickup device and the substrate voltage of the high withstand voltage drive IC are different, so that it cannot be integrated into one chip.

In view of the above, an object of the present invention is to provide a solid-state image pickup device in which the CCD solid-state image pickup element and the high withstand voltage drive IC can be integrated into one chip without deteriorating the characteristics of the CCD solid-state image pickup element. To do.

[0007]

In order to achieve the above-mentioned object, the invention of claim 1 forms a first p-type island region in which a light receiving portion, a charge transfer portion and a charge detecting portion are formed. In addition to the first P-type island region, a second p-type island region for forming a high breakdown voltage drive circuit for driving the charge transfer section is formed on the semiconductor substrate.

Specifically, the solution provided by the invention of claim 1 is the first p-type electrically isolated from each other on the n-type substrate.
A second p-type island region and a second p-type island region, and a light receiving portion, a charge transfer portion, and a charge detection portion are formed in the first p-type island region. An n-type island region is formed by implanting high-energy ions in the inside, and a drive circuit for driving the charge transfer unit is a MOSFE formed in the second p-type island region and the n-type island region.
It is composed of T.

According to a second aspect of the present invention, in order to obtain the degree of freedom in designing the drive circuit, the second p-type island region is formed by implanting high-energy ions in the configuration of the first aspect. The configuration is added.

[0010]

According to the structure of claim 1, a second p-type island region is formed on the n-type substrate having the first p-type island region electrically isolated from the first p-type island region. In addition, an n-type island region is formed in the second p-type island region, and a drive circuit for driving the charge transfer unit is constituted by the MOSFETs formed in the second p-type island region and the n-type island region. , + 5V to + 10V can be biased to the n-type substrate, 0V to the first p-type island region, -10V to the second p-type island region, and + 15V to the n-type island region.

Further, since the n-type island region is formed by implanting high energy ions, the n-type region can be formed without requiring a high temperature and long drive-in process.

Further, according to the structure of claim 2, the second p
Since the mold island region is formed by implanting high-energy ions, it is possible to obtain a degree of freedom in designing a drive circuit that drives the charge transfer unit.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic structure of a CCD solid-state image pickup device according to an embodiment of the present invention. In FIG.
Is an n-type substrate, and in the n-type substrate 1, a first p-type island region 2 and a second p-type island region 3 which are simultaneously formed and electrically isolated from each other are formed. ing. An n-type island region 4 is formed in the second p-type island region 3 by implanting high energy ions.

In the first p-type island region 2, there are two-dimensionally arranged light receiving portions 5, and vertical transfer CCs as charge transfer portions.
The D6, the horizontal transfer CCD 7, and the charge detection unit 8 are formed respectively. Further, in the second p-type island region 2, a drive circuit 9 for driving the vertical transfer CCD is formed which is composed of MOSFETs formed in the second p-type island region 2 and the n-type island region 4. There is.

The operation of the solid-state image pickup device configured as described above will be described below.

First p-type island region 2 and second p-type island region 3
Are electrically separated from each other, it is possible to bias optimum voltages to the CCD solid-state imaging device and the high breakdown voltage drive IC. That is, the first p-type island region 2 on which the CCD solid-state image sensor is formed can be biased to 0V, and the second p-type island region 3 forming the drive circuit 9 which is a high breakdown voltage drive IC has −10V. Can be biased to.

Further, since the n-type island region 4 is formed in the second p-type island region 3 and is electrically isolated from the n-type substrate 1, the n-type island region 4 and the n-type substrate 4 are formed. 1, the optimum voltage can be biased for the high withstand voltage drive IC and the CCD solid-state image pickup device. That is, the n-type island region 4 forming the drive circuit 9 which is a high breakdown voltage drive IC is +1
It can be biased to 5V, and the n-type substrate 1 is + 5V ~
It can be biased to + 10V.

N-type island region 4 which constitutes a high voltage drive IC
Must be deep in the depth direction of the n-type substrate 1 in order to maintain the breakdown voltage, and usually requires a high temperature and long drive-in step after ion implantation. This high-temperature and long-time drive-in process has a great influence on the characteristics of the CCD solid-state imaging device.

However, since the solid-state image pickup device of this embodiment forms the n-type island region 4 by high-energy implantation, it does not require a high temperature and long drive-in process. Therefore, it is possible to form the n-type island region 4 having a sufficient depth to maintain the breakdown voltage without affecting the characteristics of the CCD solid-state imaging device.

In this embodiment, the second p-type island region 3 is formed simultaneously with the first p-type island region 2, and only the n-type island region 4 in the second p-type island region 3 is formed. Although the second p-type island region 3 is formed by high-energy implantation, the design flexibility of the high breakdown voltage drive IC can be improved by forming the second p-type island region 3 by high-energy ion implantation.

[0022]

As described above, according to the solid-state image pickup device of the first aspect of the present invention, the first p-type island region is electrically connected to the n-type substrate in which the first p-type island region is formed. To form a second p-type island region, an n-type island region is formed in the second p-type island region, and a light receiving portion and a charge transfer portion are formed in the first P-type island region. And a charge detection unit, and the second
Formed in p-type island region and n-type island region
Since the drive circuit for driving the charge transfer unit is configured by the above, an optimum bias for each region, that is, a bias of +5 V to +10 V for the n-type substrate, a bias of 0 V for the first p-type island region, and a second p-type region. Since a bias of −10 V can be applied to the type island region and a bias of +15 V can be applied to the n type island region, respectively, the CCD solid-state image sensor and the high withstand voltage drive I can be applied without degrading the characteristics of the CCD solid-state image sensor.
A single chip with C becomes possible.

Further, since the n-type region is formed by implanting high-energy ions, the n-type island region can be formed without requiring a high temperature and long drive-in process. N with a sufficient depth to maintain the breakdown voltage without affecting the
It becomes possible to form a pattern island region.

Further, according to the solid-state image pickup device of the second aspect of the present invention, since the second p-type island region is formed by implanting high-energy ions, the degree of freedom in designing the drive circuit for driving the charge transfer section can be obtained. .

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a solid-state imaging device according to an embodiment of the present invention.

[Explanation of symbols]

 1 n-type substrate 2 first p-type island region 3 second p-type island region 4 n-type island region 5 light receiving part 6 vertical transfer CCD (charge transfer part) 7 horizontal transfer CCD (charge transfer part) 8 charge detection part 9 Driving circuit for driving vertical transfer CCD

Claims (2)

[Claims] 1. A first p-type island region and a second p-type island region, which are electrically isolated from each other, are formed on an n-type substrate, and a light receiving portion is formed in the first p-type island region. , A charge transfer part and a charge detection part are respectively formed, and an n-type island region is formed by implanting high-energy ions into the second p-type island region, and the drive circuit for driving the charge transfer part is 2 formed in the p-type island region and the n-type island region
A solid-state imaging device comprising an OSFET. 2. The solid-state imaging device according to claim 1, wherein the second p-type island region is formed by implanting high energy ions.