Table of Contents
Why it is advantageous to make the base thin in a BJT?
One of the ways to obtain it is to make the base thin, so that the electrons from the emitter do not spend much time in it, and therefore have less likelihood to be trapped. The emitter region is the most heavily doped area of the transistor.
Why the thickness of base region in a BJT is kept very small?
Why the width of the base region of a transistor is kept very small compared to other regions? Base region of a transistor is kept very small and very lightly doped so as to pass most of the injected charge carriers to the collector.
Why Early effect is called base width modulation?
The Early effect, named after its discoverer James M. Early, is the variation in the effective width of the base in a bipolar junction transistor (BJT) due to a variation in the applied base-to-collector voltage.
What is base current in BJT?
Base current is typically 1\% of emitter or collector current for small signal transistors. Most of the emitter electrons diffuse right through the thin base (c) into the base-collector depletion region. It is controlled by the base current, which is 1\% of the emitter current.
Why the base is lightly doped in BJT or in transistor?
Collector region of a transistor is highly doped so collector region has more width than other two. Hope you understand clearly why the base is lightly doped in bjt or in the transistor. For good amplification process, we required less base current and more collector current So we try to reduce base current by less doping of base region.
What is the β of a BJT?
Common emitter current gain, commonly denoted by β, is the ratio between collector current and base current in a bipolar junction transistor, BJT, or heterojunction bipolar transistor, HBT. Given a particular emitter and base doping, β is maximized when recombination of electrons and holes in the base is minimized.
What is the role of the base region in a BJT?
Role of Base Region of a BJT Transistor The role of the base region is to function as the trigger for a larger emitter-to-collector current. When the base current receives sufficient current, a larger current then flows from the emitter to the collector.
What is the base region of a bipolar junction transistor?
In a bipolar junction transistor, current flows from the emitter to the collector and then out from the collector. The base region of a BJT transistor is very thin and is lightly doped with current carriers. It is the region of a transistor which has opposite polarity charge carriers from the emitter and the collector regions.