Surface passivation of moderately doped and heavily doped p-type surfaces is of major importance to both p-type and n-type solar cells. Considering the practical importance and relevance of p-type Si surfaces, i.e. a moderately doped (undiffused) p-type Si surface and a heavily doped p±-type Si surface, this chapter focuses on the investigation of surface passivation using double-layer dielectric stacks. We study a positively charged dielectric stack (i.e. SiO_x capped with SiN_x) as well as a negatively charged dielectric stack (i.e., AlO_x capped with SiN_x).

Chapter Contents:

• 10.1 Introduction
• 10.2 Deposition of PECVD SiOx/SiNx and AlOx/SiNx stacks
• 10.3 Characterisation of surface passivation
• 10.3.1 Evaluation of surface passivation of undiffused and diffused Si surfaces
• 10.3.2 Evaluation of electronic interface properties
• 10.4 Investigation of moderately doped p-type silicon surfaces
• 10.4.1 Double-layer dielectric stack: PECVD SiOx/SiNx
• 10.4.1.1 Evaluation of optical properties of the PECVD SiOx films
• 10.4.2 Double-layer dielectric stack: PECVD AlOx/ SiNx
• 10.4.2.1 Importance of capping layers
• 10.4.2.2 Surface passivation mechanism
• 10.5 Investigation on heavily doped p+ silicon surface
• 10.5.1 Role of fixed charge density and extraction of Sn0 at p+ c-Si surfaces
• 10.6 Industrial Al-LBSF (or PERC) solar cells
• 10.7 Summary and conclusions
• References

Inspec keywords: dielectric thin films; silicon; solar cells; passivation; elemental semiconductors; aluminium compounds; silicon compounds; plasma CVD

Other keywords: heavily doped p⁺-type Si surface; double-layer dielectric stacks; negatively charged dielectric stack; moderately doped p-type Si surface; surface passivation; AlO-SiN; PECVD; Si; positively charged dielectric stack; silicon solar cells; SiO-SiN

Subjects: Photoelectric conversion; solar cells and arrays; Elemental semiconductors; Thin film growth, structure, and epitaxy; Surface treatment (semiconductor technology); Chemical vapour deposition; Surface treatment and degradation in semiconductor technology; Chemical vapour deposition; Solar cells and arrays; Plasma applications in manufacturing and materials processing