In this work, an emerging cell concept based on silicon homo-heterojunction (HHJ) is investigated. Compared to the n-type silicon heterojunction cell (HET), the HHJ architecture contains an additional thin and highly doped (p + )c-Si layer at the front (i)a-Si:H/(n)c-Si interface. Using numerical simulations, advantages of the alternative architecture are first underlined. Especially, passivation improvements brought by the (p + )c-Si layer are evidenced through the study of the recombination

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... tes in the whole cell. From the simulation results, the manufacturing issues of the HHJ cell are then addressed. Due to the need of a fully activated and shallow (p + )c-Si layer, ion implantation of boron is a promising candidate for making such cells. However, the efficient (i)a-Si:H passivation is very sensitive to substrate quality. Thus, the high temperature post-implantation annealing effect on the Cz substrates should to be assessed. An anneal at 1050°C, often required to fully activate Boron implanted emitters, strongly decreases the substrate lifetime and will impact drastically the HHJ cell performance. A 950°C annealing is found to limit considerably the substrate degradation. However, such rather low temperature will limit the maximum doping concentration of the implanted layer and thus the maximum achievable V OC in HHJ devices.