Nope. The natural thing about controlling the depletion zone is a field-effect transistor. That is why FETs, both metal-semiconductor FETs (with Shottky barrri

Nope. The natural thing about controlling the depletion zone is a field-effect transistor. That is why FETs, both metal-semiconductor FETs (with Shottky barrrier at the gate) and metal-insulator-semiconductor transistors have already been invented long before WWII, in 1925 and 1928, by Julius Lilienfeld (who has never succeeded to fabricate them, because the need and the means for controlling impurities were not known at that time). The fact that you can control the current through a depleted region by injection of minority carriers has never occurred to anyone before Shockley, who has thought about this only because he has searched for an explanation of the weird effect discovered by chance by Bardeen and Brattain when experimenting with multiple point contacts to a semiconductor crystal. So the discovery of the bipolar junction transistor had nothing easy and natural about it. The sequence of events at the Bell Laboratories has been: 1. The need of detector diodes for radar signals during WWII has lead to the development of growing crystals of germanium and silicon that were free from impurities, unlike any material that has ever existed before. 2. After WWII, using the materials produced by the radar research, i.e. pure germanium crystals, Bardeen, Brattain and other colleagues have made experiments with the purpose of discovering a method for making semiconductor triodes like those invented by Lilienfeld, i.e. FETs. 3. The experiments for making FETs have failed (a method of making FETs has been invented only a few years later, also by William Shockley). Nevertheless, during the experiments a weird unexplained effect has been discovered, which was named as the transistor effect (the name is not very appropriate, because a transistor is not a trans-resistor, but a trans-conductor, but that was not understood at the beginning). 4. Shockley has searched for an explanation of the origin of the transistor effect. This has lead to a theory of the semiconductor P-N junction. 5. After understanding how semiconductor P-N junctions really work and which is the role of the minority charge carriers in their properties, Shockley has invented first the bipolar junction transistor (BJT) in 1948 and then the junction field-effect transistor (JFET) in 1951, which have been the most important semiconductor devices for about a quarter of a century, until the improvements in the fabrication technology of the MOS transistors have made MOSFETs the most important semiconductor devices. Moreover, by the time of the discovery of the transistor effect, there were no junction diodes. The fabrication of junction diodes has begun later, as a byproduct of the bipolar transistor technology. Before transistors, there were point-contact diodes for radio frequencies, made with silicon, germanium, galena and many other semiconductor crystals, and also rectifier diodes made with selenium or copper oxide. The theory of these diodes was not understood well at that time, but they are metal-semiconductor diodes, i.e. Schottky diodes, not junction diodes. Shottky had given a theory of the metal-semiconductor diodes, but the theory was not helpful for designing such diodes, because it depended on material parameters that were not known at that time, so all practical diodes had been discovered empirically. Shockley has been the first to give a good theory of the junction diodes, after the discovery of the transistor effect by Bardeen and Brattain. With the Shockley theory, you could design P-N junction diodes, by controlling the impurity levels in semiconductor crystals (instead of searching experimentally for random metal-semiconductor pairs with rectifying properties, like before his theory).