JP2003224256A - Photoelectric conversion device, solid-state image pickup device, and manufacturing method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state image pickup device that can be improved in performance and, at the same time, can be manufactured through a manufacturing process increased in flexibility, and their manufacturing methods. <P>SOLUTION: A semiconductor substrate 11 is dipped in an aqueous cyano- potassium solution in a state where at least the upper part of a photoelectric conversion section 10A of the interfaces of the substrate 11 is exposed. The dangling bonds of silicon in the interfaces of the substrate 11 are terminated by cyano-ions which are not cut from their bonded dangling bonds of silicon even when the substrate 11 is subjected to a high-temperature process. Since the dangling bonds of silicon in the interfaces of the substrate 11 are sufficiently terminated by the cyano-ions, the bonds become electrically inactive and no dark current is generated near the interfaces of the substrate 11. In addition, since the dangling bonds of silicon in the interfaces of the substrate 11 are terminated by the heat-resistive cyano-ions, a cover film requiring heat treatment at a special high temperature can be formed after the dangling bonds are terminated by the cyano-ions. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric conversion device having an insulating film on a semiconductor substrate, a solid-state imaging device and a method for manufacturing the same, and more particularly to a photoelectric conversion device having an improved interface with the insulating film of the semiconductor substrate. The present invention relates to a conversion device, a solid-state imaging device, and manufacturing methods thereof.

[0002]

2. Description of the Related Art Generally, in a solid-state imaging device, an insulating film is formed on a silicon (Si) substrate. At this time, a dangling bond generated at a silicon interface between the silicon substrate and the insulating film is a device. Is known to adversely affect the operation of. For example, if a dark current is generated due to a dangling bond at the silicon interface, the performance of the device deteriorates. Therefore, it is required to reduce the dark current generated by the dangling bond at the interface of the silicon substrate. Here, the dark current is a minute current generated in a very shallow region of 0.5 μm or less from the silicon interface.

In the manufacturing process of the solid-state image pickup device, the light-shielding film formed on the charge transfer electrode is covered so as to cover the BP.
A cover film such as a protective film made of SG (Boro-Phospho-Silicate Glass) is formed. In the process of forming the cover film, a reflow process is performed by heat treatment at a temperature of 800 to 950 degrees. After this reflow step, dangling bonds at the silicon interface are hydrogen-terminated by a sintering process using hydrogen (H ₂ ) or a mixed gas of hydrogen and nitrogen (N ₂ ) in order to suppress the generation of dark current. , Si—H bond is formed to electrically inactivate the dangling bond.

In the solid-state image pickup device manufacturing process,
Although it is possible to terminate the dangling bond using fluorine (F ₂ ), fluorine is not used and hydrogen is generally used because it is a dangerous material and is difficult to handle. There is. Alternatively, in the manufacturing process of a semiconductor device, for example, JP-A-10-74753 and JP-A-200
As disclosed in JP-A-1-15772, a method for terminating dangling bonds at a semiconductor substrate interface has been proposed.

[0005]

By the way, when the hydrogen termination treatment is performed after the reflow step, the hydrogen termination of the dangling bond at the silicon interface occurs because the cover film having a large film thickness is formed on the silicon substrate. Cannot be fully converted. On the other hand, if hydrogen termination treatment is performed before the reflow step, the reflow step requires heat treatment at a high temperature of 800 ° C. or higher, so that the bondable temperature is 55.
The Si-H bond of 0 to 600 degrees or less is broken, and hydrogen termination of the dangling bond at the silicon interface cannot be sufficiently performed (Mater Integr. Vol. 13 N
o.4 2000 pp.37-43 Hikaru Kobayashi). As described above, in the method of manufacturing a solid-state imaging device in which a high temperature process is essential, the dangling bond at the silicon interface can be sufficiently terminated by the conventional method using hydrogen or a mixed gas of hydrogen and nitrogen. There is a problem that it is difficult and the dark current cannot be reduced. Note that these problems similarly apply to the photoelectric conversion device.

The present invention has been made in view of the above problems, and an object thereof is to solve the problem that the dangling bond terminated at the interface with the insulating film of the semiconductor substrate is cut after the high temperature heat treatment. It is an object of the present invention to provide a photoelectric conversion device, a solid-state imaging device, and a manufacturing method thereof, which can be solved to achieve higher performance and further increase the degree of freedom in the manufacturing process.

[0007]

A photoelectric conversion device according to the present invention has an insulating film on a semiconductor substrate, wherein a dangling bond at the interface with the insulating film of the semiconductor substrate is a compound of carbon and nitrogen, or It is terminated by the ions of the compound.

A method of manufacturing a photoelectric conversion device according to the present invention is
Forming a photoelectric conversion part on the semiconductor substrate, terminating dangling bonds at the interface of the semiconductor substrate including the upper part of the photoelectric conversion part with a compound of carbon and nitrogen or an ion of the compound, and an upper part of the photoelectric conversion part And a step of forming an insulating film on the interface of the semiconductor including.

The solid-state imaging device according to the present invention has an insulating film on a semiconductor substrate, and dangling bonds at the interface of the semiconductor substrate with the insulating film are terminated by a compound of carbon and nitrogen or an ion of the compound. It has been transformed into

A method of manufacturing a solid-state image pickup device according to the present invention is
A step of forming a photoelectric conversion part on the semiconductor substrate, a step of terminating a dangling bond at the interface of the semiconductor substrate including the upper part of the photoelectric conversion part with a compound of carbon and nitrogen or an ion of the compound; And a step of forming a first insulating film on the interface of the semiconductor including the upper portion.

In the photoelectric conversion device, the solid-state imaging device and the manufacturing method thereof according to the present invention, the dangling bond at the interface with the insulating film of the semiconductor substrate is not broken even after the high temperature process. Since the termination is performed by the compound of carbon and nitrogen or the ion of this compound, the termination of the dangling bond is not impaired even after the heat treatment process at high temperature.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. The solid-state imaging device according to the first embodiment of the present invention is embodied by the method for manufacturing the solid-state imaging device according to the present embodiment, and therefore will be described below together.

[First Embodiment] FIGS. 1 to 3 show
4 illustrates a manufacturing process of the solid-state imaging device according to the first embodiment of the present invention.

First, as shown in FIG. 1A, a silicon oxide film (Si) having a thickness of 10 to 100 nm is formed on a semiconductor substrate 11 made of N-type silicon by, for example, a thermal oxidation method.
An insulating film 12 made of O ₂ ) is formed. Next, by performing a step of implanting impurity ions by an ion implantation method and heating and diffusing the impurity ions, a mask is formed if necessary, and the ion implantation conditions and the heating conditions are repeatedly performed, , The P-type well layer 13 and the P-type charge transfer portion lower layer 1 in a predetermined region of the semiconductor substrate 11.
4, N-type charge transfer layer 15, P-type pixel separation layer 16, N-type charge storage layer 17, and P ⁺ -type surface layer 18 are formed. The N-type charge storage layer 17 and the P ⁺ -type surface layer 18 form a photoelectric conversion unit 10A.

Subsequently, as shown in FIG. 1B, a thickness of 100 to 100 is formed on the insulating film 12 by, for example, a CVD method.
A conductive film (not shown) made of polycrystalline silicon having a thickness of 200 nm is formed. Next, a lithography method is used to form a photoresist film (not shown), and the conductive film is removed by etching using the photoresist film as a mask, thereby avoiding the upper portion of the photoelectric conversion unit 10A and performing charge transfer. An opening 21A for receiving light is formed above the electrode 21 and the photoelectric conversion unit 10A. After removing the photoresist film, an insulating film 22 made of a silicon oxide film and having a thickness of 10 to 100 nm is formed on the charge transfer electrode 21 by, for example, a thermal oxidation method. Here, the charge transfer electrode 21 may have a single-layer structure or a laminated structure.

As described above, the N-type charge transfer layer 15,
In addition, the charge transfer portion 10B including the charge transfer electrode 21 formed with the insulating film 12 in between is formed. The charge transfer unit 10B includes a vertical transfer unit provided for each column of photoelectric conversion units, and a plurality of vertical transfer units provided for each column and a horizontal transfer unit vertically connected. In the charge transfer unit 10B, the signal charges are read from the photoelectric conversion unit 10A to the N-type charge transfer layer of the vertical transfer unit, and pass through the N-type charge transfer layers of adjacent pixels one after another, so that the N of the horizontal transfer unit is transferred.
Type charge transfer layer. Further, in the region of the charge transfer electrode 21 between the photoelectric conversion unit 10A and the vertical transfer unit of the charge transfer unit 10B, the read gate unit 10C is formed which is formed from the side where the P-type pixel separation layer 16 is not formed. To be done.

Next, as shown in FIG. 2A, a photoresist film (not shown) is formed by a lithography method, and the photoresist film is used as a mask to perform photoelectric conversion in the insulating film 12. The upper part of the portion 10A is selectively removed by etching.

After removing the photoresist film, the semiconductor substrate 11 is immersed in an aqueous solution of potassium cyanide (KCN). The potassium cyanide aqueous solution contains crown ether molecules for surrounding potassium (K) in the aqueous solution. After soaking in this potassium cyanide aqueous solution, the semiconductor substrate 11 is placed in boiling water and washed for about 10 minutes.
At this time, the interface of the semiconductor substrate 11, especially the semiconductor substrate 11
The silicon dangling bond in the opening 21A portion of the interface is terminated with cyano ions (CN ⁻ ) to form a Si—CN bond. This Si-CN
Since the bond is strong against heat, for example, 550 ° C or higher 85
It is not cut even after a high temperature process of 0 ° C or less.

Next, as shown in FIG. 2B, an insulating film 23 made of a silicon oxide film having a thickness of 100 to 400 nm is formed on the semiconductor substrate 11 so as to cover the charge transfer electrodes 21. To do. When forming the insulating film 23, heat treatment at a high temperature of, for example, 550 ° C. or more and 850 ° C. or less may be performed. Next, on the charge transfer electrode 21 in the insulating film 23, a light shielding film 24 made of tungsten (W) having a thickness of several hundreds nm is sequentially formed. Then, the light shielding film 24 is covered by, for example, a CVD method,
A cover film (protective film) 25 made of a BPSG film having a thickness of several hundreds nm is formed on the semiconductor substrate 11. At this time, in order to adjust the shape of the cover film 25, the temperature is set to 800 ° C to 85 ° C.
A reflow process by heat treatment or the like is performed at about 0 degrees, for example, 800 degrees. In this high-temperature heat treatment, the semiconductor substrate 11
The Si-CN bond at the interface is strong against heat and is not broken. The cover film 25 is formed by the reflow process.
A convex shape is formed in the horizontal direction with respect to the surface of the semiconductor substrate 11, and this convex shape serves as a prototype of a lens called an intralayer lens.

Finally, as shown in FIG. 3, the cover film 2
5, a flattening layer 31 of, for example, a thickness of several hundreds nm and made of a silicon nitride film (Si ₃ N ₄ ), a color filter layer 32, and a condenser lens 33 are provided so as to cover the semiconductor substrate 11. When they are sequentially formed, the solid-state imaging device 10 is completed.

In this solid-state image pickup device 10, the condenser lens 3
When light enters the photoelectric conversion unit 10A through 3, photoelectric conversion generates signal charges. The signal charges are read to the N-type charge transfer layer of the vertical transfer section of the charge transfer section 10B by applying a voltage to the read gate section 10C. A pulse voltage is applied to the charge transfer electrode 21 at a predetermined cycle to read out the signal charges, so that the N pixels of the adjacent pixels.
By successively passing through the type charge transfer layer, the charges are transferred to the N type charge transfer layer of the horizontal transfer unit which is vertically connected to the vertical transfer unit. Finally, the signal charge transferred to this horizontal transfer unit is
It is carried to an output terminal (not shown) connected to the horizontal transfer section and output as a video signal.

As described above, according to the present embodiment, the semiconductor substrate 11 is immersed in an aqueous solution of potassium cyanide while the upper part of the photoelectric conversion portion 10A of the interface of the semiconductor substrate 11 is exposed. Since the dangling bond of silicon at the interface of (4) is terminated by the cyano ion, the dangling bond of silicon at the interface with the insulating films 12 and 23 of the semiconductor substrate 11 and the cyano ion are bonded even after the high temperature process. Does not disconnect. Therefore,
The silicon dangling bond at the interface of the semiconductor substrate 11 is sufficiently terminated by cyano ions even after a high temperature process such as the process of forming the cover film 25, and thus becomes electrically inactive, so that the semiconductor Dark current does not occur near the interface between the insulating films 12 and 23 of the substrate 11. As a result, it is possible to improve the performance of the device.

Further, after the step of terminating the silicon dangling bonds at the interface of the semiconductor substrate 11 with cyano ions, the cover film 25 which requires a particularly high temperature heat treatment.
Since the termination of the dangling bonds is not impaired even if the above is formed, a step of terminating the dangling bonds at the interface of the semiconductor substrate 11 is performed not only after the high temperature process but also before the high temperature process. It can be carried out. Therefore, it is possible to further increase the degree of freedom in the manufacturing process.

[Second Embodiment] FIG. 4 is a diagram for explaining a manufacturing process of a solid-state imaging device according to a second embodiment of the present invention. In the second embodiment, the same components as those in the first embodiment are designated by the same reference numerals, the description thereof will be omitted, and different portions will be described in detail.

First, a semiconductor substrate 11 made of, for example, N-type silicon is provided with a thickness of 10 to 1 by, for example, a thermal oxidation method.
An insulating film made of a silicon oxide film having a thickness of 00 nm is formed.
Then, similarly to the first embodiment, the P-type well layer 1 is formed in a predetermined region of the semiconductor substrate 11 on which the insulating film is formed.
3, P-type charge transfer section lower layer 14, N-type charge transfer layer 15, P
The type pixel separation layer 16, the N type charge storage layer 17, and the P ⁺ type surface layer 18 are sequentially formed.

Next, after the insulating film is removed by etching, the semiconductor substrate 11 is dipped in a potassium cyanide (KCN) aqueous solution as shown in FIG. The potassium cyanide aqueous solution contains crown ether molecules for surrounding potassium (K) in the aqueous solution. This prevents potassium from moving into the semiconductor substrate 11 and eliminates the possibility that potassium will adversely affect the characteristics of the device. After soaking in this potassium cyanide aqueous solution, the semiconductor substrate 11 is placed in boiling water and washed for about 10 minutes. At this time, the silicon dangling bonds at the interface of the semiconductor substrate 11 are terminated with cyano ions, and Si-CN bonds are formed. This Si-CN
Since the bond is strong against heat, for example, 550 ° C or higher 85
It is not cut even after a high temperature process of 0 ° C or less.

Although a plurality of impurity regions are formed in the semiconductor substrate 11 and then immersed in an aqueous potassium cyanide solution, this step may not be performed after the impurity regions are formed. That is, the insulating film on the semiconductor substrate 11 may be removed by etching before the formation of the plurality of impurity regions or during the formation of the plurality of impurity regions, and then immersed in the potassium cyanide aqueous solution.

Subsequently, as shown in FIG. 4B, the semiconductor substrate 11 is formed to a thickness of 10 to 1 by, for example, a thermal oxidation method.
An insulating film 41 made of a silicon oxide film having a thickness of 00 nm is formed. Then, similarly to the first embodiment, the charge transfer electrode 21, the light receiving opening 21A, and the insulating film 22.
Are sequentially formed. Next, an insulating film 42 made of a silicon oxide film and having a thickness of 10 to 100 nm is formed on the semiconductor substrate 11 so as to cover the charge transfer electrodes 21 by, for example, a thermal oxidation method. When forming the insulating films 41, 22, 42, heat treatment at a high temperature of, for example, 550 ° C. or higher and 850 ° C. or lower may be performed.

Subsequently, as shown in FIG. 5, similarly to the first embodiment, a light shielding film 24 and a cover film (protective film) 25 are sequentially formed. At this time, in order to adjust the shape of the cover film 25, a reflow process by heat treatment or the like is performed at a temperature of about 800 to 850 degrees, for example, 800 degrees. In this high-temperature heat treatment, Si-C at the interface of the semiconductor substrate 11
The N-bond is strong against heat and is not broken. By the reflow process, the cover film 25 has a convex shape in the horizontal direction with respect to the surface of the semiconductor substrate 11, and this convex shape becomes a prototype of a lens called an intralayer lens.

Finally, as in the first embodiment,
When the flattening layer 31, the color filter layer 32, and the condenser lens 33 are sequentially formed so as to cover the cover film 25, the solid-state imaging device 50 is completed.

As described above, according to the present embodiment, the dangling bond of silicon at the interface of the semiconductor substrate 11 is formed by immersing the semiconductor substrate 11 in the potassium cyanide aqueous solution with the interface of the semiconductor substrate 11 exposed. Since the termination is performed by the cyano ion, the bond between the silicon dangling bond and the cyano ion at the interface with the insulating film 41 of the semiconductor substrate 11 is not broken even after the high temperature process. Therefore, the silicon dangling bond at the interface of the semiconductor substrate 11 is sufficiently terminated with cyano ions even after a high temperature process such as the film forming process of the cover film 25, and thus becomes electrically inactive. Therefore, no dark current is generated near the interface between the semiconductor substrate 11 and the insulating film 41. As a result, it is possible to improve the performance of the device.

Further, after the step of terminating the silicon dangling bonds at the interface of the semiconductor substrate 11 with cyano ions, the cover film 25 which requires a particularly high temperature heat treatment.
Since the termination of the dangling bonds is not impaired even if the above is formed, a step of terminating the dangling bonds at the interface of the semiconductor substrate 11 is performed not only after the high temperature process but also before the high temperature process. It can be carried out. Therefore, it is possible to further increase the degree of freedom in the manufacturing process.

[Third Embodiment] FIGS. 4A to 4C are views for explaining a manufacturing process of a solid-state imaging device according to a third embodiment of the present invention. In the third embodiment, the same components as those in the second embodiment are designated by the same reference numerals, and the description thereof will be omitted. The different portions will be described in detail.

First, similarly to the second embodiment, an insulating film 41 made of a silicon oxide film having a thickness of 10 to 100 nm is formed on the semiconductor substrate 11 made of, for example, N-type silicon by, for example, a thermal oxidation method. To do. Next, similar to the second embodiment, the P-type well layer 13, the P-type charge transfer portion lower layer 14, and the N-type charge transfer layer 15 are formed in a predetermined region of the semiconductor substrate 11 on which the insulating film 41 is formed. , P-type pixel separation layer 1
6, the N-type charge storage layer 17, and the P ⁺ -type surface layer 18 are sequentially formed.

Then, similarly to the second embodiment,
On the semiconductor substrate 11, the charge transfer electrode 21, the light receiving opening 21A, and the insulating film 22 are sequentially formed.

Then, cyano ions are implanted into the semiconductor substrate 11 by the ion implantation method. At this time, the depth of implantation of cyano ions is 1 μm from the interface of the semiconductor substrate 11.
m or less.

Then, similarly to the second embodiment,
The insulating film 42 and the light shielding film 24 are sequentially formed on the semiconductor substrate 11. When forming the insulating film 42, for example, 5
You may perform high-temperature heat processing of 50 to 850 degreeC. Then, the cover film (protective film) 25 is formed similarly to the second embodiment. At this time, in order to adjust the shape of the cover film 25, a reflow process by heat treatment or the like is performed at a temperature of about 800 to 850 degrees, for example, 800 degrees.
In this high-temperature heat treatment, the insulating film 41 of the semiconductor substrate 11 is
Since the dangling bond of silicon at the interface with and is terminated by cyano ions to form a heat-resistant Si—CN bond, the bond is not broken. The cover film 25 is formed on the semiconductor substrate 11 by the reflow process.
Is convex in the horizontal direction with respect to the surface of, and this convex shape is a prototype of a lens called an intralayer lens.

Finally, as in the second embodiment,
When the flattening layer 31, the color filter layer 32, and the condenser lens 33 are sequentially formed so as to cover the cover film 25, the solid-state imaging device 50 is completed.

As described above, according to the present embodiment, cyano ions are implanted from the interface of the semiconductor substrate 11 with the insulating film having a thickness of several tens nm being formed, so that the semiconductor substrate 1
Since the silicon dangling bond at the interface with the insulating film 41 of No. 1 is terminated by cyano ions,
Even after a high temperature process, the bond between the silicon dangling bond and the cyano ion at the interface with the insulating film 41 of the semiconductor substrate 11 is not broken. Therefore, the silicon dangling bond at the interface of the semiconductor substrate 11 is sufficiently terminated with cyano ions even after a high temperature process such as the film forming process of the cover film 25, and thus becomes electrically inactive. Therefore, no dark current is generated near the interface between the semiconductor substrate 11 and the insulating film 41. As a result, it is possible to improve the performance of the device.

Even after the step of terminating the silicon dangling bonds at the interface of the insulating film 41 of the semiconductor substrate 11 with cyano ions, the dangling is performed even if the cover film 25 requiring a high temperature heat treatment is formed. Since the termination of the bond is not impaired, the step of terminating the dangling bond at the interface between the semiconductor substrate 11 and the insulating film 41 can be performed not only after the high temperature process but also before the high temperature process. it can. Therefore, it is possible to further increase the degree of freedom in the manufacturing process.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments, and various modifications can be made. For example, in the above-described embodiment, the semiconductor substrate 11 is formed using the aqueous solution of potassium cyanide.
Although the silicon dangling bond at the interface with the insulating film is terminated by cyano ions, an aqueous solution of hydrogen cyanide (HCN) may be used. At this time, not only cyano ions but also hydrogen ions (H ⁺ )
Also terminates the silicon dangling bond at the interface with the insulating film of the semiconductor substrate 11.

Further, although the light shielding film 24 is formed by using tungsten, aluminum (Al) may be used instead. Furthermore, in the above-described embodiment, the case where the present invention is applied to a so-called solid-state imaging device has been described, but the present invention can also be applied to a photoelectric conversion device and the like.

[0043]

As described above, according to the first to fourth aspects.
According to the photoelectric conversion device described above, since the dangling bond at the interface with the insulating film of the semiconductor substrate is terminated by the compound of carbon and nitrogen such as a cyano group or the ion of the compound, high temperature Even after the process, the bond between the dangling bond of the interface silicon with the insulating film of the semiconductor substrate and the cyano ion is not broken. Therefore, the dangling bond of silicon at the interface of the semiconductor substrate becomes electrically inactive because it is sufficiently terminated by cyano ions even after a high temperature process, and becomes dark near the interface with the insulating film of the semiconductor substrate. No current is generated. As a result, it is possible to improve the performance of the device.

According to the method for manufacturing a photoelectric conversion device according to any one of claims 5 to 16, the dangling bond at the interface with the insulating film of the semiconductor substrate is formed by a compound of carbon and nitrogen such as a cyano group or a compound thereof. Therefore, the dangling bonds at the interface with the insulating film of the semiconductor substrate are terminated by the cyano ions. Therefore, the termination of the dangling bonds is not impaired even if a protective film that requires a high-temperature heat treatment is formed after the step of terminating the dangling bonds at the interface of the semiconductor substrate with cyano ions. Therefore, not only after the high temperature process but also before the high temperature process, the step of terminating the dangling bond at the interface with the insulating film of the semiconductor substrate can be performed, and the flexibility of the manufacturing process can be increased. Can be further increased.

According to the seventeenth to nineteenth aspects of the invention, the dangling bond at the interface with the insulating film of the semiconductor substrate is terminated by a compound of carbon and nitrogen such as a cyano group or an ion of the compound. Therefore, the bond between the dangling bond of the interface silicon with the insulating film of the semiconductor substrate and the cyano ion is not broken even after the high temperature process. Therefore, the dangling bond of silicon at the interface of the semiconductor substrate is electrically terminated because it is sufficiently terminated by cyano ions even after a high temperature process such as a process for forming a protective film, and thus becomes electrically inactive. No dark current is generated near the interface with the insulating film. As a result, it is possible to improve the performance of the device.

According to the method for manufacturing a solid-state image pickup device according to any one of claims 20 to 41, the dangling bond at the interface with the insulating film of the semiconductor substrate is formed by a compound of carbon and nitrogen such as a cyano group or a compound thereof. Therefore, the dangling bonds at the interface with the insulating film of the semiconductor substrate are terminated by the cyano ions. Therefore, after the step of terminating the dangling bonds at the interface of the semiconductor substrate with cyano ions,
Particularly, even if a protective film that requires a high-temperature heat treatment is formed, termination of dangling bonds is not impaired. Therefore, not only after the hot process, but also before the hot process,
The step of terminating the dangling bond at the interface with the insulating film of the semiconductor substrate can be performed, and the degree of freedom in the manufacturing process can be further increased.

[Brief description of drawings]

FIG. 1 is a process diagram for explaining a manufacturing method of a solid-state imaging device according to a first embodiment of the present invention.

FIG. 2 is a process drawing for explaining a process following FIG.

FIG. 3 is a process drawing for explaining the process following the process shown in FIG.

FIG. 4 is a process drawing for explaining the manufacturing method of the solid-state imaging device according to the second embodiment of the present invention.

FIG. 5 is a process drawing for explaining the process following FIG.

FIG. 6 is a process drawing for explaining the manufacturing method of the solid-state imaging device according to the third embodiment of the present invention.

[Explanation of symbols]

10, 50 ... Solid-state imaging device, 10A ... Photoelectric conversion unit,
10B ... Charge transfer section, 10C ... Read gate section, 1
DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate, 12, 22, 23, 41 ... Insulating film, 13 ... P-type well layer, 14 ... P-type charge transfer part lower layer, 15 ... N-type charge transfer layer, 16 ... P-type pixel separation layer, 17 ... N-type charge storage layer, 18 ... P ⁺ type surface layer,
21 ... Charge transfer electrode, 21A ... Opening, 24 ... Light-shielding film, 25 ... Cover film, 31 ... Flattening layer, 32 ...
Color filter layer, 33 ... Condensing lens

Claims (41)

[Claims] 1. A photoelectric conversion device having an insulating film on a semiconductor substrate, wherein dangling bonds at an interface of the semiconductor substrate with the insulating film are terminated by a compound of carbon and nitrogen or an ion of the compound. A photoelectric conversion device characterized in that 2. The photoelectric conversion device according to claim 1, wherein a photoelectric conversion portion is formed on the semiconductor substrate. 3. The photoelectric conversion device according to claim 1, wherein the semiconductor substrate is a silicon substrate. 4. The photoelectric conversion device according to claim 1, wherein the compound of carbon and nitrogen or the compound ion contains a cyano group or a cyano ion. 5. A step of forming a photoelectric conversion part on a semiconductor substrate, and a step of terminating a dangling bond at an interface of the semiconductor substrate including an upper part of the photoelectric conversion part with a compound of carbon and nitrogen or an ion of the compound. And a step of forming an insulating film on an interface of the semiconductor including an upper portion of the photoelectric conversion portion, the manufacturing method of the photoelectric conversion device. 6. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen, or an ion of the compound, wherein the insulating film is formed on the interface of the semiconductor substrate including the photoelectric conversion part upper portion. To form
It is performed after removing at least the upper portion of the photoelectric conversion portion of the insulating film, and after removing at least the upper portion of the photoelectric conversion portion of the insulating film, the semiconductor substrate aqueous hydrogen cyanide solution or cyano A step of immersing the semiconductor substrate in an aqueous solution of potassium cyanide or an aqueous solution of potassium cyanide, and then forming another insulating film different from the insulating film on the semiconductor substrate. The method for manufacturing a photoelectric conversion device according to claim 5, wherein. 7. The method for manufacturing a photoelectric conversion device according to claim 6, wherein the potassium cyanide aqueous solution contains crown ether molecules. 8. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound forms the insulating film at the interface of the semiconductor substrate including the photoelectric conversion part upper portion. 6. The method for manufacturing a photoelectric conversion device according to claim 5, further comprising a step of immersing the semiconductor substrate in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide before performing. 9. The method of manufacturing a photoelectric conversion device according to claim 6, wherein the semiconductor substrate is washed with boiling water after the semiconductor substrate is immersed in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide. 10. The method for manufacturing a photoelectric conversion device according to claim 8, wherein the potassium cyanide aqueous solution contains crown ether molecules. 11. The semiconductor substrate is immersed in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide, and then the semiconductor substrate is washed with boiling water.
A method for manufacturing the described photoelectric conversion device. 12. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound forms the insulating film at the interface of the semiconductor substrate including the upper portion of the photoelectric conversion section. The method of manufacturing a photoelectric conversion device according to claim 5, which is a step of terminating the semiconductor substrate after the above. 13. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound is a step of implanting cyano ions into the semiconductor substrate. 1
2. The method for manufacturing the photoelectric conversion device according to 2. 14. The other insulating film is formed at a temperature of 550 ° C. or higher and 850 or higher.
The method for manufacturing a photoelectric conversion device according to claim 6, wherein the photoelectric conversion device is formed by heating at a temperature of ℃ or less. 15. The temperature of at least one step performed after terminating dangling bonds at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound is 550 ° C. or higher and 850 ° C. or lower. The method for manufacturing a photoelectric conversion device according to claim 6. 16. The method of manufacturing a photoelectric conversion device according to claim 6, wherein the semiconductor substrate is a silicon substrate. 17. A solid-state imaging device having an insulating film on a semiconductor substrate, wherein dangling bonds at an interface of the semiconductor substrate with the insulating film are terminated by a compound of carbon and nitrogen or an ion of the compound. A solid-state imaging device characterized in that 18. The solid-state imaging device according to claim 17, wherein the semiconductor substrate is a silicon substrate. 19. The solid-state imaging device according to claim 17, wherein the compound of carbon and nitrogen or the compound ion contains a cyano group or a cyano ion. 20. A step of forming a photoelectric conversion part on a semiconductor substrate, and a step of terminating a dangling bond at an interface of the semiconductor substrate including the upper part of the photoelectric conversion part with a compound of carbon and nitrogen or an ion of the compound. And a step of forming a first insulating film on an interface of the semiconductor including an upper portion of the photoelectric conversion unit. 21. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or an ion of the compound, the first insulation at the interface of the semiconductor substrate including the photoelectric conversion part upper portion. After forming the film, it is performed after the step of removing at least the upper portion of the photoelectric conversion portion of the first insulating film, and at least the upper portion of the photoelectric conversion portion of the first insulating film is formed. The method for manufacturing a solid-state imaging device according to claim 20, further comprising the step of immersing the semiconductor substrate in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide after the removal. 22. The semiconductor substrate is immersed in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide, and then the semiconductor substrate is washed with boiling water.
1. The method for manufacturing the solid-state imaging device according to 1. 23. A step of forming a second insulating film on the semiconductor substrate after washing the semiconductor substrate with boiling water, and a light shield on the transfer electrode of the second insulating film. 3. A step of forming a film, and a step of forming a protective film on the semiconductor substrate so as to cover the light shielding film.
2. The method for manufacturing the solid-state imaging device according to 2. 24. The method for manufacturing a solid-state imaging device according to claim 21, wherein the potassium cyanide aqueous solution contains crown ether molecules. 25. The method for manufacturing a solid-state imaging device according to claim 23, wherein the protective film is a BPSG film. 26. The method for manufacturing a solid-state imaging device according to claim 23, wherein the protective film is formed by heating at a temperature of 550 ° C. or higher and 850 ° C. or lower. 27. The second insulating film is formed at a temperature of 550.degree.
24. The method for manufacturing a solid-state imaging device according to claim 23, which is formed by heating at a temperature of 0 ° C. or less. 28. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or an ion of the compound comprises: 21. The method for manufacturing a solid-state imaging device according to claim 20, further comprising a step of immersing the semiconductor substrate in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide before forming a film. 29. The method of manufacturing a solid-state imaging device according to claim 28, wherein the semiconductor substrate is washed with boiling water after being immersed in an aqueous solution of hydrogen cyanide or an aqueous solution of potassium cyanide. 30. A step of forming the first insulating film on the semiconductor substrate after washing the semiconductor substrate with boiling water, and avoiding the photoelectric conversion part on the first insulating film. Forming a transfer electrode, forming a second insulating film on the semiconductor substrate so as to cover the transfer electrode, and forming a transfer electrode of the second insulating film. 3. The method according to claim 2, further comprising a step of forming a light shielding film on the semiconductor substrate and a step of forming a protective film on the semiconductor substrate so as to cover the light shielding film.
9. The method for manufacturing the solid-state imaging device according to item 9. 31. The method for manufacturing a solid-state imaging device according to claim 28, wherein the potassium cyanide aqueous solution contains crown ether molecules. 32. The method of manufacturing a solid-state imaging device according to claim 30, wherein the protective film is a BPSG film. 33. The method for manufacturing a solid-state imaging device according to claim 30, wherein the protective film is formed by heating at a temperature of 550 ° C. or higher and 850 ° C. or lower. 34. The first insulating film is formed at a temperature of 550.degree.
29. The method for manufacturing a solid-state imaging device according to claim 28, which is formed by heating at a temperature of 0 [deg.] C. or lower. 35. The second insulating film is formed at a temperature of 550.degree.
31. The method for manufacturing a solid-state imaging device according to claim 30, which is formed by heating at a temperature of 0 [deg.] C. or less. 36. The step of terminating a dangling bond at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound is a step of implanting cyano ions into the semiconductor substrate. Item 21. A method for manufacturing a solid-state imaging device according to item 20. 37. The method of manufacturing a solid-state imaging device according to claim 36, further comprising the step of forming a protective film on the semiconductor substrate after implanting the cyano ions into the semiconductor substrate. 38. The method of manufacturing a solid-state imaging device according to claim 37, wherein the protective film is a BPSG film. 39. The method of manufacturing a solid-state imaging device according to claim 37, wherein the protective film is formed by heating at a temperature of 550 ° C. or higher and 850 ° C. or lower. 40. The temperature of at least one step performed after terminating dangling bonds at the interface of the semiconductor substrate with a compound of carbon and nitrogen or ions of the compound is 550 ° C. or higher and 850 ° C. or lower. 21. The method for manufacturing a solid-state imaging device according to claim 20. 41. The method of manufacturing a solid-state imaging device according to claim 20, wherein the semiconductor substrate is a silicon substrate.