Field effect-transistor, method for manufacturing same, wireless communication device using same, and product tag

A field-effect transistor, comprising at least:

• a substrate;
• a source electrode;
• a drain electrode;
• a gate electrode;
• a semiconductor layer in contact with said source electrode and with said drain electrode;
• and
• a gate insulating layer insulating between said semiconductor layer and said gate electrode;
• wherein said semiconductor layer contains a carbon nanotube, and
• wherein said gate insulating layer contains inorganic particles treated with a polysiloxane that has at least a structural unit represent by formula (1)
• wherein, in formula (1),
• R1 represents a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocyclic group, an aryl group, a heteroaryl group, or an alkenyl group;
• R2 represents a hydrogen atom, an alkyl group, a cycloalkyl group, or a silyl group;
• m represents 0 or 1;
• and
• A1 represents an organic group including at least two groups selected from a carboxyl group, a sulfo group, a thiol group, a phenolic hydroxy group, or a derivative of these groups, wherein, when said derivative is a cyclic condensed structure formed by two of said carboxyl group, said sulfo group, said thiol group, and said phenolic hydroxy group, A1 represents an organic group having at least one said cyclic condensed structure;
• the treatment resulting in the inorganic particles and polysiloxane being bonded together.