Grain production method for twice thinning by front cutting

Abstract

The invention discloses a crystal grain production method for twice thinning through front cutting. The production method comprises the steps of front cutting, primary fixing, primary thinning, an intermediate process, secondary thinning, adhesive removal, a metal deposition process, secondary fixing, separation from a glass carrier plate and solvent cleaning. According to the invention, through cutting, primary fixing, primary thinning, the intermediate process, secondary thinning, adhesive removal, the metal deposition process, secondary fixing, separation from the glass carrier plate and solvent cleaning, a wafer is subjected to front cutting and twice thinning to obtain crystal grains; a traditional one-time cutting mode is replaced; damage to crystal grains caused by cutting is reduced; the finished product percent of pass of the crystal grains is increased; the cutting time of a single qualified crystal grain is shortened; a traditional process of completing back yellow light, ion implantation and metal deposition before cutting is replaced; and the production cost of the crystal grains is easily controlled.

Description

technical field [0001] The invention relates to a production method, in particular to a crystal grain production method with double-thinning front cutting. Background technique [0002] An ultra-thin wafer, generally with a thickness of 20-250 microns, is used for MOSFET and IGBT power devices and 3-D devices. At present, the wafer is bonded to the glass carrier, and the glass carrier is used to transfer the wafer for wafer thinning, backside yellowing, ion implantation, metal deposition and other processes, and finally the die is cut on the die film frame And subsequent testing and packaging, it is necessary to implement yellow light, ion implantation, and metal deposition processes on the back of the thinned wafer before the wafer cutting process is performed, but the wafers that are thinned to 20 microns to 80 microns are used for cutting grains. At the same time, due to the warpage of the thin wafer, and the metal deposition of the wafer has been completed, when the ext...

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Problems solved by technology

At present, the wafer is bonded to the glass carrier, and the glass carrier is used to transfer the wafer for wafer thinning, backside yellowing, ion implantation, metal deposition and other processes, and finally the die is cut on the die film frame And subsequent testing and packaging, it is necessary to implement yellow light, ion implantation, and metal deposition processes on the back of the thinned wafer before the wafer cutting process is performed, but the wafers that are thinned to 20 microns to 80 microns are used for cutting grains. At the same time, due to the warpage of the thin wafer, and the metal deposition of the wafer has been completed, when the external force is cut, the changing stress during cutting will easily cause the wafer to crack, and the grain cannot be reworked and scrapped. Most of the prior art is cut before cutting. Complete back yellow light, ion implantation, metal deposition process, it is very easy to cause damage to the grain during cutting, which increases the production cost of the grain

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