Figure 1

Changes in τ${}_{\mathrm{eff}}$ for the different test structures. (a) Influence of low-temperature annealing in air. (b) Influence of prolonged 1-sun exposure. Measurements at Δ$n$ $=$ 1.0 × 10${}^{15}$ cm${}^{-3}$.Reuse & Permissions

Figure 2

(a) Changes in τ${}_{\mathrm{eff}}$ (Δ$n$) for an $a$-Si:H/$c$-Si(100) structure during prolonged 1-sun exposure. Symbols are measured data, solid lines are fits using recombination-model calculations. For clarity, only a few selected examples are shown. The inset shows the band diagram of the interface in (dark) thermal equilibrium, simulated with afors-het. (b) Dangling-bond density $N_{\mathrm{DB}}$ of the same structure, extracted from the fitting shown in (a). The lines are fits to power laws. Fitting parameters are $A$ $=$ 0.27 × 10${}^{15}$ cm${}^{-3}$ ${\mathrm{s}}^{-1}$ and $B$ $=$ 0.13 × 10${}^{12}$ cm${}^{-3}$ ${\mathrm{s}}^{-1}$. For reference, we also show ∼$t^{1/3}$ and ∼$t^{1/2}$ power laws.Reuse & Permissions

Figure 3

(a) Normalized τ${}_{\mathrm{eff}}$ values for $a$-Si:H/$c$-Si(100) (closed symbols) and $a$-Si:H/$c$-Si(111) (open symbols) structures during flash-light exposure. Each flash is ∼1 ms long. Measurements are evaluated at Δ$n$ $=$ 1.0 × 10${}^{15}$ cm${}^{-3}$. The lines are linear and single-exponential fits. The insets represent the two different test structures featuring identical capping films, $\gamma$, but different interfaces, $\alpha$ and $\beta$. (b) Normalized τ${}_{\mathrm{eff}}$ values for a different $a$-Si:H/c-Si(100) structure during repeated cycles of flash-light exposure, dark relaxation at room temperature and annealing (220 °C for 2 min, see arrow). (c) Calculated $N_{\mathrm{DB}}$ values corresponding to data in (b). (d) and (e) H${}_2$-effusion rate data for HF-terminated $c$-Si(111) and $c$-Si(100) surfaces, respectively, prior to film deposition. Heating rate was 20 K min${}^{-1}$. Insets show the different surface structures schematically. (f)–(h) Schematic representation of the SWE model by Carlson. See main text for explanation.Reuse & Permissions