"What did Bardeen remember? The thing we mentioned earlier—using Copper Wire to poke galena and generate an electric current."
"So Bardeen tried to improve it by using Tungsten Wire to poke silicon!"
"But that still wasn't enough. Poking it with Tungsten Wire could only achieve rectification, equivalent to a Vacuum Diode. But practical applications required amplification, equivalent to a Vacuum Triode. So they still needed to add an electrode to regulate the unidirectional current from the Tungsten Wire to the silicon wafer."
"Got it? The idea was exactly the same. They had only changed the material, doing everything they could to obtain better results through changes in materials!" Xiang Xiaotong said.
"Got it!" the students answered in unison. The lesson really was easy to follow—content even middle school students could understand.
But in truth, a true expert was skilled at explaining complex concepts in terms middle school students could understand. Only the worst teachers made concepts seem obscure and incomprehensible.
"By coincidence, Brattain's silicon wafer hadn't been stored properly and got wet from the water in the refrigerator. But it turned out to be a blessing in disguise. The damp silicon wafer unexpectedly began amplifying signals. The chemists in the group came up with a theoretical explanation, saying that the water molecules had freed the electrons on the silicon's surface from their restraints."
"So Brattain and Bardeen conducted an experiment. They poked the silicon wafer with Tungsten Wire and added a drop of water at the same time. The signal was successfully amplified!"
"But the amplification still wasn't high enough. Bardeen decided to change materials again. During the war, they learned from other research institutes that germanium could also be used to make semiconductors. So they began replacing the silicon wafers with germanium wafers. The results were astonishing: the voltage