4.2.2 Semiconductor Passivation Interface
 
On the surface of a semiconductor the periodicity of the crystal is disturbed. The vacancies of the surface bind with available elements and usually form an oxide. Most often the surface is passivated intentionally with insulator materials like Si₃N₄ or SiO₂. In all cases a charged interface is built which can be described in the simulation by a constant interface charge density Q_si. At the interface the law of Gauß holds:
 

(35)

 
where  and  are the components of the electric field perpendicular to the surface, e_s and e_i are the permittivities in the semiconductor and the insulator, respectively. The value of Q_si especially depends on the manufacturing process. Therefore it will be used as a fitting parameter within certain ranges.
 

• 4.3 Physical Parameters
• 4.3.1 Effective Mass and Band Edge Energy
• 4.3.2 Mobility

   
Next: 4.3 Physical Parameters Up: 4.2 Interface Models Previous: 4.2.1 Semiconductor Hetero Interfaces