Wafer with edge stepped/gentle slope type protection ring and manufacturing method thereof

Abstract

The invention discloses a wafer with an edge stepped / gentle slope type protection ring and a manufacturing method of the wafer. The wafer with the edge stepped protection ring comprises a wafer body,and the wafer body is provided with a grinding front surface. The periphery of the wafer body is provided with a step protection ring / slope protection ring. The preparation method comprises the stepsof pasting a grinding pasting film on the front surface of the wafer; and grinding the back surface of the wafer, using etching equipment, automatically measuring the configuration thickness by an etching process, controlling the concentration and flow of etching liquid, automatically controlling the scaling of a blocking agent by a program to protect the edge shielding ring / edge configuration inert fluid nozzle to dilute and reduce the edge etching amount, etching the back surface of the wafer, and gradually reducing the height of the protection ring from outside to inside. The ultrathin wafer structure with the protection ring is used for subsequent ion implantation, yellow light and double-sided simultaneous metal deposition processes. The front side and back side processes can be carried out at the same time in one time of production, so that the process time is saved. The ultrathin wafer structure with the protection ring reduces the lost area of an edge wafer.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a wafer with an edge stepped / gentle slope protection ring and a manufacturing method thereof. Background technique [0002] Wafer refers to the silicon wafer used in the production of silicon semiconductor integrated circuits. Because of its circular shape, it is called a wafer. It can be processed into various circuit element structures on the silicon wafer and become an IC with specific electrical functions. The product, the raw material of the wafer is silicon, and the silicon dioxide ore is refined by an electric arc furnace, chlorinated with hydrochloric acid, and distilled to produce high-purity polysilicon. After the wafer is thinned, many post-processing processes are required. To move a wafer thinned to 50-100 microns, one current method is to mechanically grind the wafer to generate a wafer with a thickness of 50-200 microns at the bottom of the wafer, leaving a 3-8 mm bor...

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Problems solved by technology

[0002] Wafer refers to the silicon wafer used in the production of silicon semiconductor integrated circuits. Because of its circular shape, it is called a wafer. It can be processed into various circuit element structures on the silicon wafer and become an IC with specific electrical functions. The product, the raw material of the wafer is silicon, and the silicon dioxide ore is refined by an electric arc furnace, chlorinated with hydrochloric acid, and distilled to produce high-purity polysilicon. After the wafer is thinned, many post-processing processes are required. To move a wafer thinned to 50-100 microns, one current method is to mechanically grind the wafer to generate a wafer with a thickness of 50-200 microns at the bottom of the wafer, leaving a 3-8 mm border ring, and then dry / wet etch The backside is treated by etching to improve the stress and poor roughness caused by mechanical grinding, and then the subsequent wafer production process begins. The circular structure generated by mechanical grinding has an almost 90-degree angle between the bottom of the wafer and the frame ring. structure, although it can meet the requirements of some subsequent production processes of thin wafers, it has the following disadvantages: the photoresist spin coating process of the yellow light process cannot be performed, because of its angular structure, the coated photoresist will be blocked by the edge Sputtering fails, and the proximity yellow light process cannot be applied. Because the proximity yellow light process requires the mask to be very close to the wafer, but it is blocked by the frame ring, and the process cannot be performed in a general and simple way, so it cannot Applying the double-sided simultaneous metal deposition process of thin wafers, in view of this situation, a method for manufacturing wafer edge step protection edge is proposed

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