Microparticle arraying mask

An apparatus comprising a microparticle arraying mask for arraying microparticles on a base material, and the microparticles, wherein

• the microparticle arraying mask has through-holes into which the microparticles are inserted,
• an opening plane of the through-holes on a microparticle supply side has an area smaller than an area of an opening plane of the through-holes on a microparticle discharge side, and
• in a case of assuming that a direction from the opening plane on the microparticle supply side to the opening plane on the microparticle discharge side is a positive direction of a z-axis, and a sectional area of the through-holes vertical to the z-axis is A,
• dA(z)/dz>0 holds in a whole region in the through-holes along the z-axis,
• Expression (1) below is satisfied:
• 0.4≤t/d<0.7 (1)
• where, in Expression (1), t indicates a thickness of the microparticle arraying mask, and d indicates the diameter of the microparticles,
• wherein the microparticle arraying mask has a thickness of less than or equal to 50 μm,
• wherein the microparticles have a diameter of less than or equal to 50 μm and are present in the through-holes, and
• a longitudinal sectional shape of the through-holes is an asymmetric shape about a central axis.