Solid-state imaging device

• US 20040259010A1
• Filed: 05/04/2004
• Published: 12/23/2004
• Est. Priority Date: 05/06/2003
• Status: Active Grant

• Current Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kanbe, Hideo
• Granted Patent: US 7,932,574 B2
• Time in Patent Office: Days
• US Class Current: 430/67
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14647 Multicolour imagers having a stacked pixel-element structure, e.g. npn, npnpn or MQW elements
• CPC Class Codes: H01L 31/02165 using interference filters, e.g. multilayer dielectric filters interference filters G02B5/28
• CPC Class Codes: H04N 25/17 Colour separation based on photon absorption depth, e.g. full colour resolution obtained simultaneously at each pixel location

Abstract

A solid-state imaging device including a substrate corresponding to a pixel. The substrate carries thereon a light receiving section, which is a stack of, in this order, a photoconductive layer for absorbing light in a wavelength region for red, a photoconductive layer for absorbing light in a wavelength region for green, and a photoconductive layer for absorbing light in a wavelength region for blue. A transparent electrode layer is provided on each of the photoconductive layers. The transparent electrode layer placed above the photoconductive layer and the transparent electrode layer placed below the photoconductive layer are sandwiching a translucent reflective layer for reflecting the light in the green wavelength region. Similarly, a translucent reflective layer is sandwiched between the transparent electrode layer placed above the photoconductive layer and the transparent electrode layer placed below the photoconductive layer for reflecting the light in the blue wavelength region. With such a structure, successfully provided is a single-plate color solid-state imaging device of a photoconductive-layer-stacked type achieving the higher color resolution and the better sensitivity.

Claims

1. A solid-state imaging device in which a substrate provided correspondingly to a pixel is carrying thereon a light receiving section that is structured by a stack of lamination layers each composed of a photoconductive layer and a transparent electrode layer thereabove, wherein

the transparent electrode layer placed between the photoconductive layers has a translucent reflective layer with which light in a predetermined wavelength region is reflected but light on a long-wavelength side is passed through.

2. The solid-state imaging device according to claim 1, wherein

between the substrate and the photoconductive layer,

in order from a side of the substrate, a light absorbing layer for absorbing the light passed through the plurality of photoconductive layers and a lower transparent electrode layer are provided.

3. The solid-state imaging device according to claim 1, wherein

between the substrate and the photoconductive layer,

in order from a side of the substrate, a reflective layer for reflecting the light passed through the plurality of photoconductive layers and a lower transparent electrode layer are provided.

4. The solid-state imaging device according to claim 1, wherein

the photoconductive layer is reduced in layer thickness toward the upper layer, and

the predetermined wavelength region reflected by the translucent reflective layer is set shorter toward the upper layer.

5. The solid-state imaging device according to claim 4, wherein

the photoconductive layers located in a middle and at a lowermost each have a layer thickness sufficient to absorb light entered thereto and reflected by the layer located therebelow.

6. The solid-state imaging device according to claim 1, wherein

the transparent electrode layer is connected with a capacitor for reading an electric charge accumulated in each of the photoconductive layers for storage.

7. A solid-state imaging device, comprising:

a first optical-electrical conversion layer;

a second optical-electrical conversion layer formed above the first optical-electrical conversion layer; and

a third optical-electrical conversion layer formed above the second optical-electrical conversion layer, wherein

a first translucent layer is formed between the first optical-electrical conversion layer and the second optical-electrical conversion layer, and

a second translucent layer is formed between the second optical-electrical conversion layer and the third optical-electrical conversion layer.

8. The solid-state imaging device according to claim 7, wherein

signals from the first, second, and third optical-electrical conversion layers are processed, and

a color signal is generated for a pixel in an imaging region.