开云体育

Unless you're getting your board made in Joe's workshop under the railway arches, you shouldn't need to worry about the manufacturability of boards with 0.2mm tracks. They're routinely used in PC motherboards, for example.

Consider for a moment tracks the on a flexi-PCB. They never break with casual flexing. Copper is very malleable, not brittle. Neglecting undercutting due to over-etching, there is no reason width would have much influence on whether the trace would be likely to break when the board was bent. The force per unit width will be the same. Of course, absolute amount of undercutting is a function of the trace thickness. So a 2oz Cu weight trace might arguably be more liable to breakage than for 0.5oz. The presumption, above, doesn't take that into account.

Track breakages are most likely where they meet the pad, because you have stress points. For thin tracks meeting big pads, consider adding teardrops. I can't remember when KiCad got them, but the feature is in version 7. For the same reason, you might avoid 90° corners.

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Regards,
Tony