Modeling of the Boron Emitter Formation Process from BCl₃ Diffusion for N-Type Silicon Solar Cells Processing

Abstract

This work is devoted to the study of boron doping diffusion process for n-type silicon solar cells applications. Deposition temperature is an important parameter in the diffusion process. In this paper we investigate its influence using an industrial scale furnace [1] (LYDOPTM Boron), which is developed by Semco Engineering. We especially used a numerical model (Sentaurus) in order to further understand the boron diffusion mechanism mainly with respect of the diffusion temperature. The model calibration is based on boron concentration profiles obtained by SIMS (Secondary Ion Mass Spectrometry) analysis. We observed that the boron profiles could be correctly simulated by a single fitting parameter. This parameter, noted kBoron which is connected to the chemical reaction kinetics developed at the interface between the boron silicon glass (BSG) and the silicon substrate

Micro-structured P–N junction surfaces: large-scale preparation, antifouling properties, and a synergistic antibacterial mechanism

“…2). The element diffusion technology 27,28 was then employed to fabricate a boron-doped n-type silicon (p + n-Si) wafer to form a p-n junction, which is beneficial for the directional transmission of charges from the material to the surface. A phosphorus-doped p-type silicon wafer (n + p-Si) was produced as well.…”

Mass production of crystalline silicon solar cells with polysilicon‐based passivating contacts: An industrial perspective

“…However, after years of continuous optimisation of the boron source and the use of oxide segregation, the proportion of interstitial boron is reduced, and the performance of the boron diffused layer is improved. 48,49 Upgrades to boron diffusion equipment can allow a much higher process uniformity is less than 5%, reaching a relatively stable mass production level. 52 Optimal design of the B diffused layer is achieved by balancing competing demands for on the one hand lower B concentration to enable better surface passivation and collection and on the other hand high B concentration to enable better lateral and contact conductivity.…”

“…In addition, when using boron bromide (BBr 3 ) as the boron source, the uniformity of boron emitter was comparatively poor, making the process a bottleneck for mass production of cells. However, after years of continuous optimisation of the boron source and the use of oxide segregation, the proportion of interstitial boron is reduced, and the performance of the boron diffused layer is improved 48,49 . Upgrades to boron diffusion equipment can allow a much higher process temperature up to 1050°C, which can significantly reduce the process time.…”

Boron-rich layer removal and surface passivation of boron-doped p–n silicon solar cells

“…PECVD or APCVD) boron doped a-SiO x and subsequently exposing it to high temperature [12][13][14] . Secondly, boron can be incorporated by ion implantation followed by high-temperature annealing [15,16] . Thirdly, a more promising technology is direct thermal diffusion of boron from a boron trichloride (BCl 3 ) [17] or BBr 3 source.…”