Manufacturing process of element chip

A manufacturing process of an element chip, comprising:

• a preparing step for preparing a substrate having first and second sides opposed to each other, and including a plurality of dicing regions and element regions defined by the dicing regions, each of the element regions containing a plurality of convex and concave portions formed above the first side of the substrate;
• a holding step for holding the substrate and an annular frame surrounding the substrate with a holding sheet adhered on the second side of the substrate;
• a protective-film forming step for forming a protective film by applying a first mixture to form a coated film above the first side of the substrate and by drying the coated film to form the protective film along the convex and concave portions, the first mixture containing a first resin and an organic solvent having a vapor pressure higher than water;
• a laser grooving step for removing the protective film along the dicing regions by irradiating a laser beam onto the protective film covering the dicing regions thereby to expose the first side of the substrate in the dicing regions;
• a dicing step for plasma-etching the substrate from the first side through the second side along the dicing regions while maintaining the protective film in the element regions thereby to dice the substrate into a plurality of element chips;
• and
• a removing step for removing the protective film in the element regions by contacting the protective film with an aqueous rinse solution.