JPH0244187B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a solid-state imaging device, and more particularly to a hybrid solid-state imaging device in which a transfer path connecting a parallel input section and a charge transfer section has good charge transfer efficiency.

(b) Background of the technology In recent years, solid-state imaging devices have made remarkable progress, and along with this, signals from photoelectric conversion elements (light receiving elements) arranged in an array can be input in parallel.
The technology of reading data using a serial-out type shift register has reached the stage of practical use.

(c) Prior Art and Problems FIG. 1 is a plan view showing the structure of a conventional solid-state imaging device. The accumulated charges gradually flow into an input diode 11 made on, for example, a second semiconductor substrate, that is, a silicon Si substrate 3. These charges are stored directly under the storage gate SG, and then transferred to the transfer gate.
When the channel directly under the TG is opened, the signals are input in parallel directly under one transfer electrode 7 in each unit pit of the CCD 12, as shown by arrow A. The charges inputted in parallel in this manner are transferred in the longitudinal direction of the CCD 12, for example, as shown by arrows B, and then read out as a time-series signal from an output diode (not shown). By the way, the shaded part 10 is the charge weir,
4, 5, 6 are other transfer electrodes constituting the CCD 12,
φ ₁ to _{φ 4} are drive pulses for the CCD 12. In addition, in FIG. 1, for convenience, the part of the light receiving element array is used as the photoelectric conversion unit 21, the part consisting of the input diode example, the storage electrode, and the transfer electrode is used as the charge parallel input part 22, and the part of the CCD 12 is used as the charge transfer part. 23 is shown.

However, in such a solid-state imaging device, as described above, the charge is input only directly under one transfer electrode, so the charge transfer path does not have the width d of the transfer electrode, and is essentially a narrow transfer path. As I get older,
Therefore, the transfer efficiency of charges from the parallel input section 22 to the charge transfer section 23 is poor, and therefore, charges may be partially left behind in the parallel input section 22. If this happens, the resolution of the captured image will eventually drop significantly.

(d) Object of the Invention The present invention has been made in view of the above-mentioned conventional drawbacks, and an object of the present invention is to provide a solid-state imaging device in which the resolution of reproduced images does not deteriorate.

(e) Structure of the Invention According to the present invention, the object is to provide a photoelectric conversion section comprising a plurality of light receiving elements on a first semiconductor substrate, and to connect the photoelectric conversion section to the photoelectric conversion section on a second semiconductor substrate. In a solid-state imaging device with a hybrid configuration comprising a charge parallel input section and a charge transfer section including a transfer section electrode gate, the charge transfer section corresponding to each light receiving element connects the charge parallel input section and the charge transfer section. Paths are provided corresponding to two or more transfer electrodes separated by at least one transfer section electrode among the unit bits of the CCD forming the charge transfer section, and when the transfer electrode is in an open state, This is achieved by a solid-state imaging device characterized by having a configuration in which charges are transferred under two or more transfer section electrodes and then transferred.

(f) Embodiments of the invention
21980), a similar invention has already been proposed in order to solve the same problem in a non-hybrid type solid-state imaging device, and the present invention is directed to a hybrid-type solid-state imaging device.

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

FIG. 2 is a plan view showing the structure of the solid-state imaging device according to the present invention, in which the same parts as in FIG. 1 are given the same reference numerals. As can be easily understood from FIG. 2, in the solid-state imaging device of the present invention, the charge transfer path between the charge parallel input section 22 and the charge transfer section 23 has a D value corresponding to the unit bit of the transfer electrode of the CCD.
(width for three electrodes in FIG. 2), which is almost the same as the width of the charge storage section 14.

Therefore, the charges stored in the portion surrounded by the charge weir 10 directly below the storage gate SG, that is, the charge storage section 14, open the transfer gate TG, and at the same time, the drive pulse φ ₁ is rolled, and the charges are transferred to Φ ₂ , Φ ₃ , Φ When ₄ is set high, all of the charge can be transferred into the unit bit of the charge transfer section 23, and almost no charge is left behind in the charge storage section 14. Therefore, when an image signal captured by this solid-state imaging device is reproduced and viewed, the resolution of the captured image hardly deteriorates.

(g) Effects of the Invention As described above in detail, since high-quality captured images can be obtained by using the solid-state imaging device of the present invention, great practical effects can be expected.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the structure of a conventional solid-state imaging device, and FIG. 2 is a plan view showing the structure of a solid-state imaging device according to the present invention. In the drawings, 1 is a multi-component semiconductor substrate, 2 is a light receiving element, 3 is a silicon substrate, 4 to 7 are transfer section electrodes of the CCD 12, and 10 is a charge weir.

Claims (1)

[Claims] 1. A transfer gate having a photoelectric conversion section 21 formed of a plurality of light receiving elements on a first semiconductor substrate 1 and connected to the photoelectric conversion section on a second semiconductor substrate 3.
Charge parallel input section 22 and charge transfer section 23 including TG
In a solid-state imaging device with a hybrid configuration, a charge transfer path corresponding to each light receiving element connecting the charge parallel input section 22 and the charge transfer section 23 is connected to a unit bit of the CCD 12 forming the charge transfer section. The transfer gate is provided corresponding to two or more transfer electrodes separated by at least one transfer electrode in the transfer gate.
A solid-state imaging device characterized in that when a TG is in an open state, charges are first transferred under the two or more transfer electrodes and then transferred.