Transistors can be structurally divided into two types: unipolar transistors and bipolar transistors. First of all, it is important to figure out how the two types of transistors work. In a bipolar transistor, take an NPN tube for example, the emitting region injects multiplet electrons into the base region to form a multiplet current aIe. the minority carrier holes in the collector region drift toward the base region under countervoltage to form a minority current Icbo. so in a bipolar transistor both carriers participate in the conductivity. And in unipolar transistor, take junction FET as an example, it is controlled the thickness of PN junction with Vgs under the applied gate source voltage, then, under the action of voltage Vds, the multiplets in N channel do drift movement, thus forming leakage current. In this process, only the multiplets are involved in the conductivity and the oligons do not play a role.
The reference to unipolar transistors is less common, and if it refers to J-FETs, I think you're missing a condition. In the use of J-FET, the PN junction is reverse biased, the principle is to use the electric field formed by the reverse bias voltage to control the channel resistance, or the number of majority carriers in the channel. the PN junction is reverse biased after only a small amount of leakage current, which is caused by poor process. The principle of the J-FET is actually closer to that of the MOSFET, which uses an insulated gate field to control the number of majority carriers in the channel. The channel current is the majority carrier current, which is different from the PN junction current, and there is no question of the majority and minority carriers matching.