Biasing in electronics means establishing predetermined voltages or currents at various points of an electronic circuit for the purpose of establishing proper operating conditions in electronic components. The AC signal applied to them is superposed on this DC bias current or voltage.
Keeping this in consideration, what do you mean by biasing of a diode?
When voltage is applied across a diode in such a way that the diode prohibits current, the diode is said to be reverse-biased. The voltage dropped across a conducting, forward-biased diode is called the forward voltage. Silicon diodes have a forward voltage of approximately 0.7 volts.
What is meant by biasing a pn junction?
The process by which, a p-n junction diode blocks the electric current in the presence of applied voltage is called reverse biased p-n junction diode. These positive ions at p-n junction (n-side) oppose the flow of positive charge carriers (holes) from p-side.