阅读说明：本技术 Cmos图像传感器晶圆的设计方法 (Design method of CMOS image sensor wafer ) 是由 赵立新 李�杰 侯欣楠 石金川 于 2018-06-28 设计创作，主要内容包括：本发明提供一种CMOS图像传感器晶圆的设计方法,包括：提供设置有若干图像传感器的晶圆；所述相邻的图像传感器具有切割道,所述切割道上有用于测试的焊盘；于所述焊盘对应于切割道的部分区域或全部区域设置间隙；在晶圆切割工艺过程中,沿所述焊盘间隙进行切割。本发明的CMOS图像传感器晶圆的设计方法,通过在焊盘对应于切割道的部分区域或全部区域设置间隙,使得晶圆切割工艺过程中,沿着焊盘间隙进行切割,降低工艺难度,节省制造成本,提高产品良率。(The invention provides a design method of a CMOS image sensor wafer, which comprises the following steps: providing a wafer provided with a plurality of image sensors; the adjacent image sensors are provided with cutting channels, and bonding pads for testing are arranged on the cutting channels; setting gaps corresponding to partial areas or all areas of the cutting channels on the bonding pads; and cutting along the bonding pad gap in the wafer cutting process. According to the design method of the CMOS image sensor wafer, the gaps are arranged in the partial areas or all areas of the bonding pads corresponding to the cutting channels, so that the wafer is cut along the gaps of the bonding pads in the process of cutting the wafer, the process difficulty is reduced, the manufacturing cost is saved, and the product yield is improved.)

1. A method for designing a CMOS image sensor wafer is characterized by comprising the following steps:

providing a wafer provided with a plurality of image sensors; the adjacent image sensors are provided with cutting channels, and bonding pads for testing are arranged on the cutting channels;

setting gaps corresponding to partial areas or all areas of the cutting channels on the bonding pads;

and cutting along the bonding pad gap in the wafer cutting process.

2. The method of designing a CMOS image sensor wafer of claim 1, wherein the wafer is cut along the middle region of the bonding pad by laser stealth.

3. The method of designing a CMOS image sensor wafer of claim 1, wherein the gap of the bonding pad is formed while etching the bonding pad.

4. The method for designing the CMOS image sensor wafer as claimed in claim 2, wherein the width of the gap is controlled during the etching of the bonding pad so that the gap is not completely etched through, and the metal on the two sides of the gap is electrically connected.

5. The method for designing a CMOS image sensor wafer as claimed in claim 1, wherein the gap of the bonding pad is realized by layout design, and the direction of the gap is consistent with the direction of the cutting street.

6. The method of claim 1, wherein the gap extends through the entire bonding pad, or wherein the gap is discontinuous and separated by metal.

7. The method of claim 1, wherein the bonding pads are comprised of multiple layers of metal, at least one of which has the gap design.

8. The method of claim 1, wherein all or a portion of the wafer thickness is cut and the wafer is expanded to form individual image sensor chips.

9. The method for designing a CMOS image sensor wafer as claimed in claim 1, wherein the width of the pad gap is smaller than a probe diameter of a pad test, and an electrical connection between the pad and the probe is ensured.

Technical Field

The invention relates to a design method of a CMOS image sensor wafer.

Background

At present, in the CMOS image sensor manufacturing process, a plurality of image sensors are usually disposed on a wafer, adjacent image sensors have dicing streets, and bonding pads for testing are disposed on the dicing streets, and during the wafer dicing process, the wafer is diced along the dicing streets to form individual image sensor chips.

Disclosure of Invention

The invention aims to provide a design method of a CMOS image sensor wafer, which reduces the process difficulty, saves the manufacturing cost and improves the product yield.

In order to solve the above technical problem, the present invention provides a method for designing a CMOS image sensor wafer, including: providing a wafer provided with a plurality of image sensors; the adjacent image sensors are provided with cutting channels, and bonding pads for testing are arranged on the cutting channels; setting gaps corresponding to partial areas or all areas of the cutting channels on the bonding pads; and cutting along the bonding pad gap in the wafer cutting process.

Preferably, the wafer is cut along the middle region of the bonding pad by means of laser stealth.

Preferably, the gap of the pad is formed while etching the pad.

Preferably, in the process of etching the bonding pad, the width of the gap is controlled, so that the gap is not completely etched through, and the metals on the two sides of the gap are electrically communicated.

Preferably, the gap of the pad is realized by layout design, and the direction of the gap is consistent with the direction of the cutting path.

Preferably, the gap extends through the entire pad, or the gap is discontinuous with metal therebetween.

Preferably, the pad is composed of multiple layers of metal, at least one of which has the gap design.

Preferably, all or part of the thickness of the wafer is cut, and the wafer is subjected to expansion to form a single image sensor chip.

Preferably, the width of the pad gap is smaller than the diameter of a probe for pad test, so that the electrical connection between the pad and the probe is ensured.

According to the design method of the CMOS image sensor wafer, the gaps are arranged in the partial areas or all areas of the bonding pads corresponding to the cutting channels, so that the wafer is cut along the gaps of the bonding pads in the process of cutting the wafer, the process difficulty is reduced, the manufacturing cost is saved, and the product yield is improved.

Drawings

Fig. 1 is a schematic top view of a CMOS image sensor according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view taken along line B-B of FIG. 1;

FIG. 3 is a partial schematic view of a CMOS image sensor according to one embodiment of the invention;

FIG. 4 is a partial schematic view of a CMOS image sensor according to another embodiment of the invention;

fig. 5 is a partial schematic view of a CMOS image sensor according to yet another embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather construed as limited to the embodiments set forth herein.

Next, the present invention is described in detail by using schematic diagrams, and when the embodiments of the present invention are described in detail, the schematic diagrams are only examples for convenience of description, and the scope of the present invention should not be limited herein.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

The invention provides a design method of a CMOS image sensor wafer, which comprises the following steps: providing a wafer provided with a plurality of image sensors; the adjacent image sensors are provided with cutting channels, and bonding pads for testing are arranged on the cutting channels; setting gaps corresponding to partial areas or all areas of the cutting channels on the bonding pads; and cutting along the bonding pad gap in the wafer cutting process.

Fig. 1 is a schematic top view of a CMOS image sensor according to an embodiment of the present invention, in which two adjacent image sensors S1 and S2 on a wafer are shown as an example, the adjacent image sensors S1 and S2 have streets a-a, pads 110 for testing are disposed on the streets a-a, and gaps 120 are disposed in regions of the pads 110 corresponding to the streets a-a, so that during a wafer dicing process, dicing is performed along the pad gaps 120.

The gap 120 of the pad 110 may be implemented by layout design, and the direction of the gap 120 is the same as the direction of the cutting street a-a, so that the gap 120 of the pad 110 is formed while etching the pad 110 in the manufacturing process of the image sensor.

Referring to fig. 2, preferably, during the etching process of the pad 110, the width W of the gap 120 is controlled so that the gap 120 is not completely etched through, so that the metals 110 on both sides of the gap are electrically connected, thereby facilitating the smooth test.

In addition, the width W of the pad gap 120 is smaller than the diameter of the probe for pad test to ensure the electrical connection between the pad 110 and the probe, thereby facilitating the smooth test.

Preferably, the bonding pad 110 is made of multiple layers of metals, wherein at least one layer has the design of the gap 120, so as to facilitate the cutting process, thereby achieving the purpose of reducing the difficulty of the process.

In a preferred embodiment as shown in fig. 3, a gap is provided to the pad 110 in all regions 120 corresponding to the scribe line a-a, i.e., the gap 120 extends through the entire pad 110.

In another preferred embodiment as shown in fig. 4, a gap is provided in a partial area 220 of the pad 210 corresponding to the cutting street a-a, and the partial area 220 is continuous.

In another preferred embodiment as shown in fig. 5, a gap is provided in a partial area 320 of the pad 310 corresponding to the scribe line a-a, and the partial area 320 is discontinuous and separated by metal.

In summary, in the method for designing the CMOS image sensor wafer of the present invention, the gaps are disposed in the partial regions or all regions of the bonding pads corresponding to the dicing streets, so that the wafer is diced along the gaps of the bonding pads during the dicing process, thereby reducing the process difficulty, saving the manufacturing cost, and improving the yield of the product.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make variations and modifications of the present invention without departing from the spirit and scope of the present invention by using the methods and technical contents disclosed above.