Method for Uniformly Coating Insulation Layer on Inner Wall of TSV

Abstract

The invention discloses a method for coating a silicon through hole inner wall with an insulation layer. The surface of a wafer and the interior of a silicon through hole are cleaned through a cleaning process; the surface of the wafer and the interior of the silicon through hole are rotationally coated with an organic solvent capable of dissolving high-performance polymer materials in advance, then the surface of the wafer and the interior of the silicon through hole are rotationally coated with high-temperature polymer materials, and the high-performance polymer materials are evenly diffused under the effect of the organic solvent, so that the silicon through hole side wall is evenly coated with the insulation layer. According to the method, the wafer surface and the wafer silicon through hole side wall and bottom can be evenly coated with the insulation layer on standard rotary coating equipment through the general technology at normal temperature, the micron dimension silicon through hole three-dimensional even coating is achieved, the equipment cost is greatly saved, the uniformity of the silicon through hole insulation layer is improved, and binding force between the insulation layer and materials making contact with the insulation layer is improved.

Description

technical field [0001] The invention relates to the field of wafer level chip scale packaging (WLCSP) technology of semiconductor chips, in particular to a method for uniformly coating the inner wall of a through-silicon hole with an insulating layer. Background technique [0002] Wafer level chip scale packaging (wafer level chip scale packaging, WLCSP) is a kind of IC packaging method. It is a packaging method that first packages the entire wafer and then cuts it to obtain a single chip. Using through-silicon via technology to expose the pins on the front of the metal chip, that is, the PIN pins, from the back of the wafer, and then electrically lead them to the back of the wafer, the size of the chip after packaging can be kept unchanged, and it has an extremely short The electrical transmission distance makes the chip run faster and the power is reduced. [0003] The through-silicon via (TSV) technology needs to insulate the inner wall of the through-silicon via before ...

AI Technical Summary

Problems solved by technology

At present, the TSV industry generally uses plasma-enhanced chemical vapor deposition (PECVD) equipment to achieve the coating of the inorganic insulating layer, but PECVD equipment is expensive, and the temperature of the inorganic insulation process is relatively high, which is not suitable for the process temperature required by the image sensor. Technical indicators below 200 degrees

However, the existing commonly used spin coating equipment has strict requirements on the viscosity of insulating materials, and the spraying method is difficult to ensure that the entire inner wall of the TSV can be coated evenly to achieve good insulation.

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