Electronic device member of metallic structure and non-metallic structure, and method for manufacturing same

An electronic device, comprising:

• a front plate;
• a back plate facing away from the front plate;
• a touch screen display exposed through the front plate;
• an outer metal structure surrounding a space between the front plate and the back plate, and formed integrally with the back plate or coupled to the back plate;
• an inner metal structure connected with or formed integrally with the outer metal structure, and arranged in the space;
• an inner non-metal structure coupled with the outer metal structure and the inner metal structure and arranged in the space;
• at least one recess formed in one surface of the inner metal structure;
• and
• a polymer structure formed in the one surface of the inner metal structure by filling the at least one recess with a polymeric material, and connected with or formed integrally with the inner non-metal structure, and comprising a plurality of scales,
• wherein the at least one recess is extended to have a repeating pattern comprising at least one of a W-shape, a sawtooth shape, a planar rectangular spiral shape, or a planar circular spiral shape,
• wherein the at least one recess comprise a first area and a second area that is disposed closer to an opening than the first area, and
• wherein a width of the second area is bigger than a width of the first area.