Abstract: Gradation exposure is performed on an insulating layer by irradiating the insulating layer with exposure light using a photomask having a partial light-transmitting region that is configured to be partially transmittable of the exposure light. After the gradation exposure, development processing is performed on the insulating layer such that a recess is formed in a portion of the insulating layer that has been irradiated with the exposure light through the partial light-transmitting region. The partial light-transmitting region of the photomask has a plurality of first holes that are transmittable of the exposure light and a plurality of second holes that are arranged to surround the plurality of first holes and transmittable of the exposure light, and the area of each second hole is larger than the area of each first hole.

Abstract: A thick portion having a first thickness and a thin portion having a second thickness on a base insulating layer are formed on a conductive support substrate. The second thickness is smaller than the first thickness. A boundary surface is formed between an upper surface of the thick portion and an upper surface of the thin portion. A boundary line between the upper surface of the thick portion and the boundary surface extends in a first direction. Write wiring traces and read wiring traces are formed to extend on the thick portion and the thin portion of the base insulating layer. The lateral sides of the write wiring traces and the read wiring traces extend in a second direction that intersects with the first direction, and the second direction forms an angle of not less than 60 degrees and not more than 90 degrees with the first direction.

Abstract: Read wiring traces and write wiring traces are formed on an insulating layer that is formed on a support substrate. Connection terminals that are electrically connectable to external circuits are formed at parts of the read wiring traces and write wiring traces on the insulating layer, respectively. Openings are formed in the support substrate so as to partially or entirely surround overlap regions that overlap with the connection terminals and have the same plane shape as the connection terminals. Parts of the insulating layer are exposed in the openings.

Abstract: A thick portion having a first thickness and a thin portion having a second thickness on a base insulating layer are formed on a conductive support substrate. The second thickness is smaller than the first thickness. A boundary surface is formed between an upper surface of the thick portion and an upper surface of the thin portion. A boundary line between the upper surface of the thick portion and the boundary surface extends in a first direction. Write wiring traces and read wiring traces are formed to extend on the thick portion and the thin portion of the base insulating layer. The lateral sides of the write wiring traces and the read wiring traces extend in a second direction that intersects with the first direction, and the second direction forms an angle of not less than 60 degrees and not more than 90 degrees with the first direction.

Abstract: Read wiring traces and write wiring traces are formed on an insulating layer that is formed on a support substrate. Connection terminals that are electrically connectable to external circuits are formed at parts of the read wiring traces and write wiring traces on the insulating layer, respectively. Openings are formed in the support substrate so as to partially or entirely surround overlap regions that overlap with the connection terminals and have the same plane shape as the connection terminals. Parts of the insulating layer are exposed in the openings.

Abstract: Gradation exposure is performed on an insulating layer by irradiating the insulating layer with exposure light using a photomask having a partial light-transmitting region that is configured to be partially transmittable of the exposure light. After the gradation exposure, development processing is performed on the insulating layer such that a recess is formed in a portion of the insulating layer that has been irradiated with the exposure light through the partial light-transmitting region. The partial light-transmitting region of the photomask has a plurality of first holes that are transmittable of the exposure light and a plurality of second holes that are arranged to surround the plurality of first holes and transmittable of the exposure light, and the area of each second hole is larger than the area of each first hole.