## 2 Materials and Methods
### Types of Cleaning Agents for Wafer Dicing on the Market  
There are many cleaning agents available on the market. Each supplier has their own specific formula and instructions, but regardless, they can be classified into four categories, as shown in Table 2. The first type is a pure solvent. The second type is an alkaline solution. The third type is an alkaline agent with surfactant. The fourth type is known as a photoresist stripper. In this study, we also tested the performance of seven types of commercial cleaning agents. It was found that both SP-700 stripper and buffered oxide etch (BOE) (HF + NH\({}_{4}\)F) effectively removed Level 1 silicon contaminants (Table 3), while the other agents failed. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Type** & **Solvent-Based** & **Alkaline-Based** & **Alkaline +** & **Stripper** \\  & & & & **Surfactant** & **(Photoresist)** \\ \hline Products & Triton: X-100 & Developer (D05) & \begin{tabular}{c} GDC03 \\ (Alkaline) \\ \end{tabular} & \begin{tabular}{c} Stripper (SP-700) \\ \end{tabular} \\ \hline Formula & & & 0.5\% TMAH & Petroleum ether & 8\% TMAH (25\%) \\  & & 0.05\% non-ionic & \
\begin{tabular}{c} Amine base \\ surfactant \\ \end{tabular} &
\begin{tabular}{c} 85\% DMSO \\ 7\% Sorbitol \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Four types of cleaning agents on the market that are applied to the dicing process. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & & & & \multicolumn{5}{c}{Performance} \\  & & 1. & Level 1\(\sim\)3 contamination cleaning performance: Full cleaning is good, otherwise no good. & 2. & Al corrosion: No corrosion is good, otherwise no good. & 3. & UBM under cut: No more under cut is good. & Less than 1 um under cut is acceptable but needs to be improved; over 1 um under cut will be treated as no good. & 4. & Gel residue: No residues is good, otherwise no good. & 5. & 6. & 7. & 8. & 9. & 10. \\ \cline{3-10} Test & Type of Cleaner & & & & & & & & & \\ \cline{3-10}  & & & & & & & & & & \\ \cline{3-10}  & & & & & & & & & & \\ \cline{3-10}  & & & & & & & & & & \\ \cline{3-10}  & & & & & & & & & & \\ \hline \multirow{2}{*}{Test} & Triton & \multirow{2}{*}{X-100} & \multirow{2}{*}{NG} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{NG} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} \\  & & & & & & & & & & \\ \hline \multirow{2}{*}{2} & Developer & \multirow{2}{*}{(D05)} & \multirow{2}{*}{NG} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{NG} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} & \multirow{2}{*}{OK} \\  & & & & & & & & & \\ \hline \multirow{3}{*}{3} & Alkaline + & \multirow{3}{*}{40\% NG} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{20\% NG} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{NG} \\  & Surfactant & & & & & & & & \\ \cline{3-10}  & & & & & & & & & \\ \cline{3-10}  & & & & & & & & & \\ \hline \multirow{3}{*}{4} & Stripper & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{50\% NG} & \multirow{3}{*}{NG} \\  & & & & & & & & \\ \cline{3-10}  & & & & & & & & \\ \hline \multirow{3}{*}{5} & SC-1 & NG & NG & OK & NG & NG & NG & NG \\ \cline{3-10}  & & SC-2 & NG & NG & OK & NG & NG & OK & OK \\ \hline \multirow{3}{*}{7} & BOE (HF & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} & \multirow{3}{*}{NG} & \multirow{3}{*}{OK} & \multirow{3}{*}{OK} \\  & buffer) & & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Comparison of the performance of different cleaning agents. Although the stripper was capable of removing Level-1 silicon contamination, it was more aggressive and corrosive, even against ink marks, tape adhesives residues, IC metals, etc.