The mechanical fragility of thinner silicon has broadly stalled the progression toward even thinner wafers/cells. It's a pity since the optically/electronically optimum thickness would be thinner than is common now, and thinner wafers would yield more wafers per ingot.

Do you know how Jinko is handling such thin wafers when they assemble their own modules? If they're making cells of such thinness they presumably have found a way to do it; nobody can afford to accidentally break half of their cells on the way to modules.