No difference in appearance! But for the same chip area, 7nm has more transistors. Therefore, compared with 14nm chip and 7nm chip, the number of transistors is a lot less, in fact, the area of 14nm chip and 7nm chip is not very large, so the former number of transistors is a lot less, in terms of performance and power consumption will be worse.
The appearance difference is 4 times the size. The former is four times the latter.