KR20100079556A - Cmos image sensor and method for manufacturing the same - Google Patents

Abstract

PURPOSE: A CMOS image sensor and a manufacturing method thereof are provided to prevent particles by coating a planarization layer of an image sensor on a contact part with a solder ball. CONSTITUTION: An interlayer insulation layer includes a metal wiring(120) which is opened on a semiconductor substrate. A color filter array is formed on the side of an interlayer insulation layer. A planarization layer(150) is formed on the interlayer insulation layer adjacent to the metal wiring and the color filter array. A micro lens corresponds to the color filter array on the planarization layer. A solder ball(170) is mounted on the metal wiring to be electrically connected. The planarization layer reduces stress when the solder ball is mounted.

Description

CMOS image sensor and its manufacturing method {CMOS IMAGE SENSOR AND METHOD FOR MANUFACTURING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to semiconductor devices, and in particular, to a CMOS image sensor and a manufacturing method thereof.

In general, an image sensor is a semiconductor device that converts an optical image into an electrical signal. A charge coupled device (CCD) includes a charge carrier having a capacitor in which individual MOS capacitors are in close proximity to each other. The CMOS image sensor uses a CMOS technology that uses a control circuit and a signal processing circuit as peripheral circuits to make MOS transistors as many as the number of pixels and uses the switching method of sequentially detecting outputs. It is an element to employ | adopt.

1A and 1B are cross-sectional views of a typical CMOS image sensor.

As shown in FIG. 1A, the interlayer insulating film 11, the passivation film 12, the color filter layer 13, and the color filter layer 13 are planarized on the semiconductor substrate 10 including a photodiode (not shown). A planarization layer 14 and a microlens 15 are included, and metal wires 16 are formed on the side of the adjacent semiconductor substrate 10 to electrically connect the CMOS image sensor.

In addition, as shown in FIG. 1B, a solder ball 17 is formed on the metal wire 16 to be electrically connected to an external substrate (not shown).

However, the portion A of the interlayer insulating film 11 and the passivation film 13 in the region adjacent to the metal wiring 16 to which the solder balls 17 are hit, as in the prior art, is hard around the solder balls 17. Because of the presence of materials, they are easily broken when under stress, causing cracks or particles.

The technical problem to be achieved by the present invention is to manufacture a CMOS image sensor, by applying a planarization film of the CMOS image sensor to the contact portion of the solder ball, it is possible to reduce the stress and prevent the generation of particles.

According to an embodiment of the present disclosure, a method of manufacturing a CMOS image sensor may include forming an interlayer insulating film including an open metal wire on a semiconductor substrate, and forming a color filter array on the interlayer insulating film. Forming a planarization layer on the interlayer insulating film adjacent to the color filter array and the metal wiring; forming a microlens corresponding to the color filter array on the planarization layer; and electrically connecting the metal wiring. And mounting the solder balls.

According to another embodiment of the present disclosure, a CMOS image sensor may include an interlayer insulating film including a metal wiring opened on a semiconductor substrate, a color filter array formed on a side surface of the interlayer insulating film, and an interlayer insulating film adjacent to the color filter array and the metal wiring. And a planarization layer formed on the planarization layer, and solder balls mounted on the planarization layer to be electrically connected to the microlenses and metal wires corresponding to the color filter array.

In the CMOS image sensor and a method of manufacturing the same according to an embodiment of the present invention, in manufacturing the CMOS image sensor, by applying a planarization film of the CMOS image sensor to the contact portion of the solder ball, it is possible to relieve stress and to prevent particle generation Can be.

Hereinafter, the technical objects and features of the present invention will be apparent from the description of the accompanying drawings and the embodiments. Looking at the present invention in detail.

Hereinafter, the CMOS image sensor according to an exemplary embodiment of the present invention will be described with reference to FIG. 2E.

The CMOS image sensor according to the exemplary embodiment of the present invention may include an interlayer insulating film 110, a metal wiring 120 formed in the interlayer insulating film 110, and a passivation layer 130 formed on the interlayer insulating film 110. ), A color filter array 140, a planarization layer 150, a microlens 160, and a solder ball 170.

The solder ball 170 may be formed on the metal line 120 to connect an electrical signal to the CMOS image sensor.

The planarization layer 150 is formed on the color filter array 140. The planarization layer, which was conventionally formed only on the color filter array 140, is formed on the entire surface of the upper substrate adjacent to the substrate on which the metal wiring 120 is formed. Is formed.

This is to reduce the stress the substrate receives during solder ball mounting in subsequent processes.

That is, the planarization layer 150 is formed on a substrate adjacent to the metal wiring 120 to buffer the solder ball to prevent cracking and particle generation.

Hereinafter, a method of manufacturing a CMOS image sensor according to an exemplary embodiment of the present invention will be described with reference to FIGS. 2A to 2E. A manufacturing method of the CMOS image sensor will be described.

2A through 2E are cross-sectional views of processes for manufacturing a CMOS image sensor according to an exemplary embodiment of the present invention.

 As shown in FIG. 2A, an optical sensing unit including a photodiode (not shown) is formed on the semiconductor substrate 100.

In detail, the optical sensing unit including the photodiode is formed on the semiconductor substrate 100, and an isolation layer (not shown) defining an active region and a field region is formed, and each unit pixel receives light. Photodiodes for generating photocharges are formed, and transistors (not shown) connected to the photodiodes to convert the received photocharges into electrical signals are formed.

After forming the device isolation layer and related elements including the photodiode, an interlayer insulating layer 110 is formed on the semiconductor substrate 100, and then a metal wiring 120 is formed in the interlayer insulating layer 110. The metal wires 120 are laid out so as not to block light incident on the photodiode.

The metal wire 120 may be formed of aluminum or copper.

As shown in FIG. 2B, the passivation layer 130 is formed on the entire surface of the semiconductor substrate 100.

The passivation layer 130 may be formed on the interlayer insulating layer 110 to protect the device from moisture, scratches, and the like, and the passivation layer 130 on the metal line 120 may be removed.

The passivation layer 130 may be formed of any one of a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, or may have a structure in which one or more layers are stacked.

Preferably, the passivation layer 130 may be formed in a structure in which the TEOS film is formed to a thickness of 1,000 to 5,000 GPa, and the nitride film is laminated to a thickness of 1,000 to 10,000 GPa.

As shown in FIG. 2C, the color filter 140 is formed on the passivation layer 130. The color filter array 140 is formed of three color filters 140 for realizing a color image, and a material of the color filter array 140 is dyed photoresist, one for each unit pixel. The color filter array 140 is formed to separate the color from the incident light.

Meanwhile, without forming the passivation layer 130, the color filter array 140 may be formed on the interlayer insulating film 110 on which the metal wiring 120 is formed by a subsequent process, which affects the overall height of the image sensor. It may also provide a thinner, smaller image sensor.

Each of the color filter arrays 140 represents a different color, and is composed of three colors of red, green, and blue, and adjacent color filter arrays 140 overlap each other to have a step.

As shown in FIG. 2D, the planarization layer 150 is formed on the color filter array 140 as a follow-up process to compensate for the problem. In the present invention, the planarization layer formed only on the color filter array 140 is used in the present invention. The metal wiring 120 is formed on the entire surface of the upper substrate adjacent to the substrate.

This is to reduce the stress the substrate receives during solder ball mounting in subsequent processes.

That is, the planarization layer 150 is formed on a substrate adjacent to the metal wiring 120 to buffer the solder ball, thereby preventing cracks and particles.

 As shown in FIG. 2E, the photoresist film is coated on the planarization layer 150, and then patterned and the microlens 160 is formed through a reflow process. The microlens is the color filter array 140. To correspond to.

Then, the solder ball 170 is formed on the metal wiring 120. Forming the solder ball 170, for example, can be made on the metal wiring 120 by the printing method, if the pitch of the solder ball 170 is a large mask can be used, if the pitch is fine photosensitive film It can form by the method of using a resist.

In the CMOS image sensor and a method of manufacturing the same according to an embodiment of the present invention, in manufacturing the CMOS image sensor, by applying a planarization film of the CMOS image sensor to the contact portion of the solder ball, it is possible to relieve stress and to prevent particle generation Can be.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and various substitutions, changes and modifications can be made without departing from the spirit of the present invention. It will be apparent to those who have knowledge.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

1A and 1B are cross-sectional views of a process for forming a general CMOS image sensor.

2A-2E are cross-sectional views of a process for forming a CMOS image sensor in accordance with an embodiment of the present invention.

Claims (5)

Forming an interlayer insulating film including an open metal wiring on the semiconductor substrate; Forming a color filter array on the interlayer insulating film; Forming a planarization layer on the interlayer insulating film adjacent to the color filter array and the metal wiring; Forming a microlens corresponding to the color filter array on the planarization layer; And Mounting a solder ball to be electrically connected to the metal wire; Method of manufacturing a CMOS image sensor comprising a. The method of claim 1, The planarization layer is Method of manufacturing a CMOS image sensor, characterized in that formed to buffer the stress when the solder ball is mounted. The method of claim 1, The solder ball is Method of manufacturing a CMOS image sensor, characterized in that formed by a printing method using a photosensitive film resist. An interlayer insulating film including a metal wiring open on the semiconductor substrate; A color filter array formed on a side surface of the interlayer insulating film; A planarization layer formed on the interlayer insulating film adjacent to the color filter array and the metal wiring; A micro lens corresponding to the color filter array on the planarization layer; And A solder ball mounted to be electrically connected to the metal wire; CMOS image sensor, characterized in that it comprises a. The method of claim 4, wherein The planarization layer is CMOS image sensor, characterized in that buffering the stress when the solder ball is mounted.

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