Semiconductors

Definition

Semiconductors are materials that have electrical conductivity between that of conductors and insulators. They are essential in the development of electronic devices, as their ability to control the flow of electric current makes them key components in transistors, diodes, and integrated circuits. Understanding semiconductors is fundamental to grasping how electronic devices operate, including their applications in various fields and how their properties change with temperature.

5 Must Know Facts For Your Next Test

1. Semiconductors can be intrinsic (pure) or extrinsic (doped), with extrinsic semiconductors being more widely used due to improved conductivity.
2. Common semiconductor materials include silicon (Si), germanium (Ge), and gallium arsenide (GaAs), each having specific applications based on their properties.
3. Temperature significantly affects the conductivity of semiconductors; as temperature increases, more charge carriers become available, enhancing conductivity.
4. Semiconductors are foundational for modern electronics, enabling the functionality of devices such as smartphones, computers, and solar cells.
5. The invention of the transistor in 1947 marked a pivotal moment in electronics, leading to the miniaturization and increased performance of devices through the use of semiconductors.

Review Questions

• How do semiconductors differ from conductors and insulators in terms of electrical properties?
  • Semiconductors have electrical conductivity that lies between conductors, which allow current to flow freely, and insulators, which resist current flow. Their unique ability to control current makes them versatile for various applications. While conductors have a high number of free charge carriers, semiconductors can increase their conductivity through doping or by changing temperature conditions, allowing them to adapt to different electronic functions.
• Discuss how doping affects the properties of semiconductors and why it is important for electronic applications.
  • Doping involves introducing impurities into a semiconductor material to alter its electrical properties. This process creates either p-type or n-type semiconductors, allowing for better control over electrical current. The ability to customize conductivity levels through doping is crucial for creating components like diodes and transistors, which are essential in all modern electronics. The right level of doping ensures that devices operate efficiently under varying conditions.
• Evaluate the impact of temperature on semiconductor behavior and its implications for electronic device performance.
  • Temperature plays a significant role in determining how semiconductors function. As temperature rises, thermal energy excites electrons, increasing the number of charge carriers available for conduction. This phenomenon can enhance performance but also leads to challenges such as increased leakage currents and thermal runaway in devices. Therefore, understanding and managing temperature effects is vital for ensuring reliability and efficiency in semiconductor-based electronics across various applications.

Related terms

Doping:

The process of adding impurities to a semiconductor to change its electrical properties, enhancing its conductivity.

Band Gap: The energy difference between the valence band and the conduction band in a semiconductor, which determines its electrical conductivity.

PN Junction: A boundary formed between p-type and n-type semiconductors, crucial for the operation of diodes and transistors.