Is it better to study semiconductors before electronics devices?
How a transistor or diode behaves can be described entirely at the level of currents, voltages, resistance and capacitance and so on, except for the most subtle fine points.  Electronics-only classes will suffice for this, and for using transistors and other devices effectively in practical circuitry.

Why a semiconductor device behaves the way it does, and designing them, does require deeper knowledge including quantum mechanics, condensed matter physics, band theory and all that.