To terminate polishing at an appropriate position, an end point position of the polishing is sensed. According to one embodiment, a method that chemomechanically polishes a substrate including a functional chip is provided. The method includes: a step of disposing the functional chip on the substrate; a step of disposing an end point sensing element on the substrate; a step of sealing the substrate on which the functional chip and the end point sensing element are disposed with an insulating material; a step of polishing the insulating material; and a step of sensing an end point of the polishing based on the end point sensing element while the insulating material is polished.