Semiconductor Electronics Overview

<p>They gain energy and enter the conduction band. (A)</p> Signup and view all the answers

<p>A vacancy in the valence band with a positive charge. (C)</p> Signup and view all the answers

<p>Temperature and electron mobility (A)</p> Signup and view all the answers

<p>Increases the number of free electrons and holes. (D)</p> Signup and view all the answers

<p>To modify electrical properties using impurities. (C)</p> Signup and view all the answers

<p>The conduction band is partially filled. (A)</p> Signup and view all the answers

<p>The energy required to move electrons from the valence band to the conduction band. (A)</p> Signup and view all the answers

<p>Electrons in solids have overlapping orbits. (A)</p> Signup and view all the answers

<p>Each electron is affected by a unique pattern of surrounding charges. (A)</p> Signup and view all the answers

<p>Insulators (D)</p> Signup and view all the answers

<p>It is partially filled with electrons that can easily move. (B)</p> Signup and view all the answers

<p>Electrons can share energy levels with neighboring atoms. (B)</p> Signup and view all the answers

<p>It is typically partially filled and can contain free electrons. (A)</p> Signup and view all the answers

<p>They diffuse into the n-region. (D)</p> Signup and view all the answers

<p>Drift current (B)</p> Signup and view all the answers

<p>The net current becomes zero. (C)</p> Signup and view all the answers

<p>Electric field development (C)</p> Signup and view all the answers

<p>Movement of charge carriers from high concentration to low concentration. (B)</p> Signup and view all the answers

<p>It flows in the same direction as the applied voltage. (C)</p> Signup and view all the answers

<p>They allow for current to enter and exit the diode. (A)</p> Signup and view all the answers

<p>Expansion of the depletion region. (B)</p> Signup and view all the answers

<p>Holes (A)</p> Signup and view all the answers

<p>Trivalent impurities (D)</p> Signup and view all the answers

<p>They are equal in charge. (A)</p> Signup and view all the answers

<p>Tin (C)</p> Signup and view all the answers

<p>1.1 eV (A)</p> Signup and view all the answers

<p>Diamond &gt; Silicon &gt; Germanium (C)</p> Signup and view all the answers

<p>It becomes p-type. (B)</p> Signup and view all the answers

<p>Germanium (A)</p> Signup and view all the answers

<p>The reverse current increases sharply. (A)</p> Signup and view all the answers

<p>Reverse current is independent of reverse voltage up to a critical value. (D)</p> Signup and view all the answers

<p>It converts alternating current to direct current. (D)</p> Signup and view all the answers

<p>It reduces the number of majority carriers reaching the junction. (D)</p> Signup and view all the answers

<p>Both the current and the voltage at the specified operating points. (D)</p> Signup and view all the answers

<p>A few µA (C)</p> Signup and view all the answers

<p>The diode current increases significantly. (B)</p> Signup and view all the answers

<p>0.7 V (B)</p> Signup and view all the answers

<p>It is constant and very small. (B)</p> Signup and view all the answers

<p>As the ratio of small change in voltage to small change in current. (A)</p> Signup and view all the answers

<p>Microammeter (B)</p> Signup and view all the answers

<p>Current increases rapidly after reaching a threshold voltage. (D)</p> Signup and view all the answers

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The Bohr model explains the energy levels of electrons in an isolated atom, determined by their orbits. However, when atoms come together to form a solid, the orbits of electrons from neighboring atoms interact, leading to a unique energy level for each electron.

The distinct energy levels that electrons occupy within a solid create energy bands. The valence band consists of the energy levels of electrons in the outermost shell, while the conduction band contains higher energy levels accessible to free electrons.

The energy gap (Eg) is the energy difference between the top of the valence band and the bottom of the conduction band. This energy difference determines the electrical conductivity of a material.

In conductors or metals, the conduction band is either partially filled or overlaps with the valence band. This allows electrons to easily move and conduct electricity.

In insulators, the energy gap (Eg) is very large, making it difficult for electrons to jump from the valence band to the conduction band. This makes them poor conductors of electricity.

The energy difference between the valence band and conduction band in a semiconductor.

The band of energy levels in a semiconductor where electrons are tightly bound to atoms and cannot conduct electricity.

The band of energy levels in a semiconductor where electrons are loosely bound and can move freely, allowing for electrical conductivity.

A material whose conductivity increases with temperature because more electrons gain enough energy to jump from the valence band to the conduction band.

A pure semiconductor material with no impurities added intentionally.

A semiconductor material with impurities added intentionally to modify its electrical properties.

An empty state in the valence band of a semiconductor, created when an electron jumps into the conduction band.

The process of an electron gaining energy and moving from the valence band to the conduction band, resulting in a free electron and a hole.

A semiconductor, like silicon, doped with a trivalent impurity (e.g., boron) which creates an excess of holes (electron vacancies). These holes act as majority carriers, enabling improved electrical conductivity.

The energy difference between the valence band (electrons bound to atoms) and the conduction band (electrons free to move and conduct) in a semiconductor.

The inherent conductivity of a semiconductor material at room temperature, determined by the inherent number of free electrons and holes present.

The conductivity of a semiconductor enhanced by doping with impurities to increase either the number of electrons (n-type) or holes (p-type).

The ability of a material to conduct electricity, determined by the availability of free charge carriers (electrons or holes) to transport electric current.

Elements like carbon (diamond), silicon, and germanium whose conductivity lies between that of a conductor and an insulator, and can be altered by doping to control their properties.

The process of adding impurities to a semiconductor to alter its conductivity.

The number of free electrons in a semiconductor, higher in n-type semiconductors and lower in p-type semiconductors, typically expressed in units like m^-3.

The current flowing in a diode in the reverse bias condition is practically independent of the reverse voltage applied, until it reaches a critical voltage known as the breakdown voltage.

The breakdown voltage (Vbr) is the critical reverse voltage at which the reverse current in a diode starts to increase rapidly.

Rectification refers to the process of converting alternating current (AC) into direct current (DC).

A diode is a semiconductor device that allows current to flow in only one direction.

A rectifier is a circuit that uses diodes to convert AC to DC.

The movement of charge carriers (electrons or holes) in a material due to an electric field. In semiconductors, this flow of charge is typically caused by the drift of electrons in the conduction band and holes in the valence band.

The voltage at which a diode starts to conduct significantly in the forward direction. This threshold voltage is typically around 0.2V for germanium diodes and 0.7V for silicon diodes.

The relationship between voltage and current for a diode in forward bias. As the voltage increases, the current increases exponentially, exceeding the threshold voltage. This is the region where the diode conducts significantly.

The relationship between voltage and current for a diode in reverse bias. The current remains very small and relatively constant even with increasing reverse bias voltage. This current is known as the reverse saturation current.

The small current that flows through a diode in reverse bias. This current is generally very small compared to the forward bias current.

A parameter that describes how much the current changes in relation to the applied voltage in a diode. It is a constant with change in bias.

The ratio of the change in voltage to the change in current in a diode, calculated in the forward bias region. It is a small change in voltage to a small change in current.

The process of increasing the forward bias voltage until the diode reaches the threshold voltage where significant current is flowing.

The movement of charge carriers in a semiconductor from a region of high concentration to a region of low concentration.

The region near the junction of a p-n semiconductor where the electric field is strongest. This region forms due to the diffusion of charge carriers across the junction and creates a barrier for further diffusion.

The junction formed when a p-type semiconductor is joined with an n-type semiconductor. This junction is the key element of diodes and transistors. It is like a two-way highway for charges, but only allows current to flow in one direction.

A semiconductor diode under forward bias allows current to flow easily. This occurs when a positive voltage is applied to the p-side and a negative voltage to the n-side, reducing the depletion region and allowing charges to flow freely.

A semiconductor diode under reverse bias prevents current from flowing. This occurs when a negative voltage is applied to the p-side and a positive voltage to the n-side, increasing the depletion region and creating a barrier for current flow.

The process of adding impurities to an intrinsic semiconductor to alter its electrical properties. This allows the creation of p-type semiconductors (by adding acceptor impurities) or n-type semiconductors (by adding donor impurities).

A semiconductor device that allows current to flow in only one direction. It consists of a p-n junction with metallic contacts for external voltage application. This device is crucial in rectifying AC current and controlling voltage.