Photocharge Transport and Recombination Measurements in Amorphous Silicon Films and Solar Cells by Photoconductive Frequency Mixing: Annual Subcontract Report, 20 April 1999 - 19 April 2000 Page: 6 of 41

                                
List of Figures

Figure 1. Samples G202 and G179, dilution ratio is kept constant at 1:5.
Figure 2. Samples G203 and G204, dilution ratio is kept constant at 1:5.
Figure 3. Samples 170426 and 180929.
Figure 4. Samples P60715I with flat and rough surface; These are prepared by
employing the "uninterrupted growing/annealing" technique.
Figure 5. Sample schematics for measurements in two field directions.
Figure 6. DC and AC currents with perpendicular contact geometry(Film thickness
5244A).
Figure 7. Field dependent mixing power for both configurations. For the TCO-a-Si:H-
Al sample, the zero-field point was shifted according to the mixing power minimum at
V = -0.5V (Fig. 6).
Figure 8. Light-induced changes in photoconductivity, mobility, and lifetime of film
R8796 (H2 diluted, using RF).
Figure 9. Light-induced changes in photoconductivity, mobility, and lifetime of film
R8794 (H2 diluted, using VHF).
Figure 10. Photo current for nip-devices in the annealed state.
Figure 11. Square root of mixing signal for nip-devices in the annealed state.
Figure 12. Normalized decay of the dc photocurrent in short circuit condition, and the
back-bias mixing signal in nip device R8791.
Figure 13. Normalized decay of the dc photocurrent in short circuit condition and the
back-bias mixing signal in nip device R8792.
Figure 14. Normalized decay of the dc photocurrent in short circuit condition and the
back-bias mixing signal in nip device R8793.
Figure 15. Light-induced changes of photoconductivity, mobility, and lifetime for
sample MVS 968.
Figure 16. The photoconductivity as a function of deposition rate.

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