Method for preventing chip back metal peeling

Abstract

The invention discloses a method for preventing the metal on the back of a chip from being stripped, which comprises the steps that: the thinning process is applied to the back of the chip adopting apredetermined number of microsections and the damaged silicon layer on the back of the chip is removed using the chemical corrosion solution; the chip is washed using the water so as to remove the residual sully. The method disclosed by the invention can prevent the metal on the back of the chip from being stripped, and can be used for accurately deciding whether the phenomenon of metal strippingexists. The use of the corrosion method effectively removes the damaged silicon layer so as to reduce the mechanical stress. The adoption of the method of controlling the process temperature in the process of evaporization reduces the stress mismatch of the Ti, Ni and Ag three different metals so as to realize solving the problem of the metal stripping on the back of the chip without causing the organic sully.

Description

technical field [0001] The invention relates to a method for metallizing the back of a chip in a semiconductor manufacturing process, more specifically, a method for preventing metal peeling off on the back of a chip in a semiconductor manufacturing process. Background technique [0002] There are many methods for backside metallization of chips. Magnetron sputtering and electron beam evaporation are the most commonly used methods for backside metallization, and their processes have been widely used. Deposition by magnetron sputtering has a high degree of automation, but the throughput is relatively low, and it is an ideal process method below 0.6 μm. In contrast, the method of electron beam evaporation has the following advantages: [0003] 1) The deposited film has high purity and less sodium ion pollution; [0004] 2) Since the evaporation source is only vaporized near the center of the surface, there is no contamination of the crucible; [0005] 3) The integration pro...

AI Technical Summary

Problems solved by technology

Generally speaking, in order to increase the contact area between the metal layer and the silicon substrate, it is often used to increase the roughness on the back of the silicon wafer. The greater the roughness, the larger the contact area between the metal layer and the silicon substrate, but at the same time Mechanical damage and stress will also increase significantly, resulting in increased fragmentation rates and wafer deformation

At the same time, due to the presence of a large amount of silicon shavings and damaged layers on the surface of the silicon wafer after grinding, the adhesion between the deposited metal film and the substrate decreases and peeling occurs. At the same time, due to the existence of stress, it is possible to Spalling occurs between metal films (usually Ti / Si or Ni / Ag) over time

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