A dicing method for protecting sensitive structures of MEMS devices

Abstract

The invention discloses a scribing method for protecting sensitive structures of MEMS devices. The scribing method comprises the steps of: adopting a silicon wafer with a protective structure as a protective sheet; cooperating the silicon wafer with the MEMS wafer to be sliced ​​through an assembly structure provided thereon, and then performing scribing and splitting successively. A single MEMS device is obtained; when the silicon wafer is mated with the MEMS wafer, each MEMS device on the MEMS wafer is embedded in the protective structure of the silicon wafer. When the method of the invention is adopted, during the scribing and slitting process, the silicon shavings generated by slicing are blocked by the chamber wall of the protection chamber; the silicon shavings generated by slicing are blocked by the scribing grooves around the MEMS device. Compared with the prior art, the method of the present invention has the advantages: the protective wafer is processed by one-step etching to realize the protection of the MEMS structure, the process flow and operation are simple, and the wafer can be reused; no expensive scribing is required Chip equipment can be realized on the basis of existing process equipment, with low cost; it can be applied to various MEMS devices and has strong applicability.

Description

technical field [0001] The invention relates to a MEMS device scribing method, in particular to a scribing method for protecting sensitive structures of the MEMS device. Background technique [0002] With the development of the IC and MEMS industry, the dicing technology has been greatly improved. In the manufacturing process of MEMS devices, it is necessary to divide the wafer by dicing to obtain the required single MEMS devices. The common wafer dicing methods are Dicing knife scribing and laser scribing, but silicon chips and other debris are usually generated during the scribing process. For non-wafer-level packaged devices, these debris can easily enter the sensitive structure of the MEMS device during the scribing process , making the function of the device invalid, seriously affecting the yield. [0003] In the prior art, for non-wafer level packaged devices, the chip is usually cleaned when the wafer is diced or after dicing. However, MEMS structures usually contai...

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Problems solved by technology

However, MEMS structures usually contain micron-level gaps. Liquids entering sensitive structures will cause adhesion between structures and damage devices. In addition, it is difficult to remove silicon powder on the surface.

In 2004, S.H.Tseng et al. in Taiwan mentioned the use of thick photoresist to protect the MEMS structure. After scribing, chemical reagents were used to remove the photoresist and then dried. However, this method also faced problems after the MEMS structure was exposed to the cleaning solution. The failure problem, and it is difficult to remove the photoresist for the lower layer of the structure; in addition, there is also a technology that first scribes until the base layer of the device is about to crack, then releases the structure, and finally splits to obtain a single chip. This method avoids the cleaning liquid from contacting the MEMS sensitive structure. , but there will still be debris entering the sensitive structure when the lobes

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