JUNCTIONLESS TRANSISTOR

Presented By:Nipun C P07104114S7 ECE-B

Overview

•History of transistor.• Introduction to the world of Junctionless.•Design Considerations.•Fabrication.

History

•When was transistor principle invented?•1947…..

• Sorry.•Way before………..•In 1925……..•By a physicist named Julius Edgar

Lilienfield.

Lilenfield Device

Design ConsiderationsThe key requirements in the transistor Full depletion when turned off.

Reasonable amount of current flow when turned on.

Full depletion thin and narrow semiconductor layerHigh current flow Heavy doping

The traditional transistor fails when the size reduces to nano dimensions(shall see later…).

Construction

Fabrication

Different stages stages: 1. Channel Fabrication. 2. Gate Fabrication.

3. Providing electrical contact to device.

Channel FabricationSOI WAFERS

• E- Beam Lithography

Silicon nanowires

• Dimension in the range of few tens of nano meter

Gate FabricationLPVCD Reactor

• Deposition of Si at high temperature

Doping

• Boron or Arsenic

V-I Characteristics

Comparison with MOS devices

Domains of comparison

Subthreshold slopeMobility