## 3 Results and Discussions
### Energy Deposited Difference between Neutrons and Protons  
In addition to LET, the energy deposition in the total devices is important for the study of SEE. Since a proton is an ionizing radiation, it releases energy when it passes the target. The energy deposited in the detection layer was calculated and shown in Tables 5 and 6 for structures with and without SiGe. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **LANSCE** & **63 MeV** & **105 MeV** & **150 MeV** & **200 MeV** & **230 MeV** \\  & **Neutron** & **Proton** & **Proton** & **Proton** & **Proton** & **Proton** \\ \hline EI & 0 & 0.550 & 0.541 & 0.524 & 0.381 \({}^{*}\) & 0.533 \\ \hline \hline \end{tabular} \({}^{*}\) Indicates the best choice.  
\end{table} 
Table 4: EI for secondary particle yields in layer structure with SiGe. Figure 8: The secondary particle yields in the structure with and without SiGe irradiated by 63 and 230 MeV protons and LANSCE neutron. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **LANSCE** & **63 MeV** & **105 MeV** & **150 MeV** & **200 MeV** & **230 MeV** \\  & **Neutron** & **Proton** & **Proton** & **Proton** & **Proton** & **Proton** \\ \hline EI & 0 & 0.237 & 0.256 & 0.258 & 0.228 \({}^{*}\) & 0.257 \\ \hline \hline \end{tabular} \({}^{*}\) Indicates the best choice.  
\end{table} 
Table 3: EI for LET in layer structure with SiGe. For the case without SiGe, Table 5 shows that 63 MeV protons are found to have more events with LET \(>\) 1 and 10 MeV-cm\({}^{2}\)/mg than other incident particles, and they also cause the most energy deposition. This is expected as the lower energy will result in higher deposited energy since the stopping power is inversely proportional to the kinetic energy [24]. Calculating the energy deposited for generating an event, 200 MeV and 230 MeV give better efficiency (i.e., lower dose with higher LET counts). In comparison to neutrons, proton irradiation gives off over 200 times more energy deposited. Compared to the results of structures with (Table 5) and without (Table 6) SiGe, both LANSCE neutron and protons show the differences on energy deposited and event number. For LET \(>\) 1 MeV-cm\({}^{2}\)/mg, a decrease of 4% in the secondary particle yields is observed, and for LET \(>\) 0 MeV-cm\({}^{2}\)/mg, the decrease is 20% in the LANSCE neutron case. These decreases are due to the presence of germanium which has a larger neutron absorption cross-section than other materials in this study [25; 26]. In the proton cases, 63 MeV proton also has a 4% decrease in secondary yields from LET \(>\) 1 MeV-cm\({}^{2}\)/mg and a 6% decrease for LET \(>\) 10 MeV-cm\({}^{2}\)/mg. For 230 MeV proton, however, the secondary yield does not lead to a decrease, but rather to an increase both with LET \(>\) 1 MeV-cm\({}^{2}\)/mg and LET \(>\) 10 MeV-cm\({}^{2}\)/mg. This is because of the spallation which generates heavy secondary ions in the cases of proton irradiation. This spallation has its cross-section positively correlate to the incident energy and the \(Z\) of the target [19]. \begin{table}
\begin{tabular}{c c c c c c c} \hline  & **LANSCE** & **63 MeV** & **105 MeV** & **150 MeV** & **200 MeV** & **230 MeV** \\  & **Neutron** & **Proton** & **Proton** & **Proton** & **Proton** & **Proton** \\ \hline Energy deposited (GeV) & 2.4761 & 15,956 & 10,706 & 8232.0 & 6765.3 & 6181.3 \\  & & & & & & \\  & & & & & & \\  & & & & & & \\  & & & & & & \\ \end{tabular}
\end{table} 
Table 6: Energy deposition analysis results for the layer structure with SiGe for 10\({}^{10}\) neutron/proton incident. \begin{table}
\begin{tabular}{c c c c c c c} \hline  & **LANSCE** & **63 MeV** & **105 MeV** & **150 MeV** & **200 MeV** & **230 MeV** \\  & **Neutron** & **Proton** & **Proton** & **Proton** & **Proton** \\ \hline Energy deposited (GeV) & 2.7019 & 15,910 & 10,680 & 8213.4 & 6750.3 & 6165.4 \\  & & & & & & \\  & & & & & & \\  & & & & & & \\  & & & & & & \\ \end{tabular}
\end{table}