Rectifying and Ohmic Contacts

  • Badih El-Kareh
  • Lou N. Hutter


A contact between metal and silicon can be rectifying or ohmic. The most commonly used rectifying contact is the Schottky barrier diode (SBD). Because of its fast response to signals, the SBD has found several applications in analog circuits where switching speed is important. A contact is said to be ohmic, i.e., non-rectifying, if it exhibits negligible resistance to current in both voltage polarities. Most semiconductor devices are interconnected on the chip and brought to the “outside world” by means of ohmic contacts and metal wires. Understanding the physical nature of contacts and methods to reduce their resistance is becoming increasingly important as contact dimensions are reduced. The first part of this chapter discusses SBD properties, characterization, and applications. The second part describes the formation and characterization of ohmic contacts.

Supplementary material


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Badih El-Kareh
    • 1
  • Lou N. Hutter
    • 2
  1. 1.PIYECedar ParkUSA
  2. 2.Lou Hutter ConsultingDallasUSA

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