## 3 Analysis and Discussion
The green lines represent the total signal caused by both sources: \(s_{g}\) = 6 ms\({}^{-1}\) (solid line), \(s_{g}\) = 10 ms\({}^{-1}\) (dashed line), and \(s_{g}\) = 14 ms\({}^{-1}\) (dash-dotted line). surface recombination velocities, the dominance of recombination sources does not occur for the \(s_{g}>10\) ms\({}^{-1}\) (Figure 6). Based on this observation, it can be concluded that the slopes of the time-domain temperature signal--both the rising slope following the leading edge of the optical pulse and the falling slope following the trailing edge--are influenced by the electronic properties of the semiconductor, particularly the diffusion coefficient of the minority carriers. An increase in the diffusion coefficient results in a slower rise and fall of the signal and consequently a smaller maximum value for the same surface recombination velocities. It is interesting to note that the results presented in Figures 5 and 6 indicate that the complex function describing the time-domain temperature signal in thermally thin and plasma-opaque samples (Equation (47)) can, in fact, be approximated by a linear function. The electronic parameters of silicon (such as the minority carrier lifetime and their diffusion coefficient) primarily influence the slope of the linear function. Figure 7 illustrates the normalized time-domain temperature signal for a thermally thin and plasma-transparent n-doped silicon sample (\(l_{s}=20\) um, \(D_{p}=1.2\times 10^{-3}\) m\({}^{2}\)s\({}^{-1}\)). The red line represents the signal originating from the thermalization of the lattice (a fast heat source), while the blue lines show the signal resulting from surface recombinations for \(s_{b}=6\) ms\({}^{-1}\) and various \(s_{g}\) values. The green lines depict the total signal generated by both sources (\(s_{g}=6\) ms\({}^{-1}\) as a solid line and \(s_{g}=14\) ms\({}^{-1}\) as a dashed line)  
As seen in Figure 7, the time-domain temperature signal from the plasma-transparent sample behaves similarly to that of the plasma-opaque sample in terms of shape, settling time, and dependence on \(s_{g}\). However, for the plasma-transparent sample, the slopes of both the rising and falling edges are also affected by the surface recombination velocity \(s_{b}\). This results in a slower rise of the signal, leading to significantly lower maximum signal values when all other electronic and thermal parameters remain constant. To further investigate the impact of \(s_{b}\), Figure 8 presents the time-domain temperature signal for a thermally thin and plasma-transparent n-doped silicon sample (\(l_{s}=20\) um, \(D_{p}=1.2\times 10^{-3}\) ms\({}^{-1}\)) with a fixed \(s_{g}=2\) ms\({}^{-1}\). The value of the surface recombination velocity on the unilluminated side, \(s_{b}\), was varied. The red line indicates the signal resulting from thermalization of the lattice (a fast heat source), while the blue lines show the signal from surface recombinations for \(s_{g}=2\) m/s at different \(s_{b}\) values. The green lines represent  
Figure 6: The normalized time-domain temperature signal for a thermally thin and plasma opaque p-doped silicon sample. The red line represents the signal resulting from lattice thermalization (fast heat source), while the blue lines indicate the signal from surface recombinations at different \(s_{g}\) values. The green lines represent the total signal caused by both sources: \(s_{g}=6\) ms\({}^{-1}\) (solid line), \(s_{g}=10\) ms\({}^{-1}\) (dashed line), and \(s_{g}=14\) ms\({}^{-1}\) (dash-dotted line). the total signal caused by both sources, with \(s_{b}\) = 6 ms\({}^{-1}\) indicated by a solid line and \(s_{b}\) = 24 ms\({}^{-1}\) by a dashed line. As seen in Figure 8, the increase in \(s_{b}\) influences both the slope of the time-domain temperature signal and the maximum value the signal reaches just before the falling edge of the optical pulse, similar to the effect observed with an increase in \(s_{g}\).