Shortcut Methods
Shortcut Methods and Tricks
1. Integer values:
- $$V_0=0.7V$$ for Si $$P-N$$junction
- $$V_0=0.3V$$ for Ge $$P-N$$junction
- Depletion width $$W=10^{-4}cm\ \text{for Si P-N junction}$$
- Depletion width $$W=10^{-3}cm\ \text{for Ge P-N junction}$$
- Drift Velocity $$v_d=10^7\ cm/s$$
2. Conceptual understandings:
- Drift current is indeed proportional to the applied voltage.
- Barrier potential $$V_0$$ is indeed temperature-dependent.
- The depletion region width does increase with increasing reverse bias voltage.
- The electric field in the depletion region is indeed uniform.
- The electric potential is constant in the neutral regions, as we expect.
- The potential difference across the junction is equal to the sum of the built-in potential and the applied bias voltage.
- The current-voltage characteristic of a $$P-N$$ junction diode is indeed nonlinear.
- The diode is said to be forward biased when the $$P-N$$ junction is connected to a battery with the positive terminal connected to the $$P$$-side and the negative terminal connected to the $$N$$-side, and reverse biased when the $$P-N$$ junction is connected to a battery with the positive terminal connected to the $$N$$-side and the negative terminal connected to the $$P$$-side.
- The diode is said to be in the breakdown region when the reverse bias voltage exceeds a certain value, called the breakdown voltage, just as you said.
