i have a component (RFMD IC 50 Ohm matched) which i will solder on a pcb with transmission line width of 1.5 mm (50 ohm impedance).
The legs of that component is .5 mm long so it will be soldered like this
So it covers half the transmission line. Will there be any problem of matching as component leg in not covering the whole width of transmission line
There is no problem with component legs but be sure that stripline ( 1.5 mm wide ) is really a 50 ohms line, only here you would have a problem . And must be as short as posible. Working frequency Vs PCB type , that's more important.
As long if the component does not introduce any impedance discontinuity is not necessarily to use any step-change width. So, for a simple capacitor you can let as it is.