What occurs if reverse voltage exceeding the absolute maximum rated emitter-base voltage is applied to the base terminal of bipolar junction transistors (BJTs) ?

Bipolar transistors have the highest concentration in the emitter, followed by the base, then the collector. The concentration of the emitter is over 100 times higher than that of the base. The higher the concentration, the lower the withstand voltage tends to be.
V_EBO has only a few volts. Care must be taken when inputting a large-amplitude signal to the base. In addition, reverse bias is applied to some circuits such as the circuit below. Please consider the usage conditions when designing.
When a monostable multivibrator is composed of bipolar junction transistors (BJTs), a bias voltage exceeding the rated V_EBO might be applied to the base.
The following describes the operation of the multivibrator shown in Fig. 1.

1. Suppose that Q₁ is initially on. Therefore, the collector voltage of Q₁ is close to the GND level. C₁ is charged via R₃ while C₂ is charged via R₂.
2. As C₁ is charged, the base-collector voltage of Q₂ reaches its turn-on voltage
   (roughly 0.7 V), turning it on. The collector voltage of Q₂ drops to a level close to GND. Immediately before this point, the voltage across C₂ is charged at V_CC – 0.7 V. Even when the collector voltage of Q₂ drops, C₂ remains charged. Therefore, the voltage at the C₂ terminal on the base side of Q₁ drops to 0.7 V – V_CC. These steps are repeated to act as a monostable multivibrator. Suppose that V_CC = 10 V. Then, the emitter-base voltage of Q₁ and Q₂ reaches -9.3 V, exceeding the rated V_EBO of -5 V.