Wafer thinning tape and preparation method thereof, and wafer grinding method

A preparation method for a wafer thinning tape, wherein:

• the wafer thinning tape comprises:
• a tape layer, a base film layer, and a conductive coating, wherein the tape layer, the base film layer, and the conductive coating are successively stacked,
• the base film layer and the conductive coating constitute an antistatic base film;
• raw materials of the tape layer consist of an acrylic adhesive, a curing agent, and an antistatic agent, a mass dosage of the curing agent is 3%-4% of a mass dosage of the acrylic adhesive, and a mass dosage of the antistatic agent is 1%-2% of the mass dosage of the acrylic adhesive;
• the base film layer is a thermoplastic polyurethane (TPU) film;
• the conductive coating is a silver nanowire coating;
• the curing agent is toluene 2,4-diisocyanate;
• the antistatic agent is pyridinium, alkyl-alkyl-, salt with polyhalogeno-[(polyhalogenoalkyl) sulfonyl]alkanesulfonamide, wherein an impedance of the antistatic base film is equal to or less than 102 ohm, and a silver nanowire used in the silver nanowire coating has a diameter of 25-300 nanometers;
• the preparation method comprises:
• mixing the acrylic adhesive, the curing agent, and the antistatic agent according to parts by mass to obtain a tape layer slurry;
• coating the tape layer slurry on a release film, and drying to form the tape layer on the release film;
• coating a silver nanowire on a first side of the base film layer, and drying to form the conductive coating on a surface of the base film layer;
• and
• affixing the tape layer to a second side of the base film layer to obtain the wafer thinning tape.

A wafer grinding method comprising a wafer thinning tape, wherein:

• the wafer thinning tape comprises:
• a tape layer, a base film layer, and a conductive coating, wherein the tape layer, the base film layer, and the conductive coating are successively stacked,
• the base film layer and the conductive coating constitute an antistatic base film;
• raw materials of the tape layer consist of an acrylic adhesive, a curing agent, and an antistatic agent, a mass dosage of the curing agent is 3%-4% of a mass dosage of the acrylic adhesive, and a mass dosage of the antistatic agent is 1%-2% of the mass dosage of the acrylic adhesive;
• the base film layer is a thermoplastic polyurethane (TPU) film;
• the conductive coating is a silver nanowire coating;
• the curing agent is toluene 2,4-diisocyanate;
• the antistatic agent is pyridinium, alkyl-alkyl-, salt with polyhalogeno-[(polyhalogenoalkyl) sulfonyl]alkanesulfonamide, wherein an impedance of the antistatic base film is equal to or less than 102 ohm, and a silver nanowire used in the silver nanowire coating has a diameter of 25-300 nanometers;
• the wafer grinding method comprises:
• first affixing the tape layer of the wafer thinning tape to a non-grinding surface of a wafer, and then grinding the wafer.