how to combine two tables in one table in order to show data in better form?

Question

I wanted to combine these two tables. I want one table with three rows and five columns. The first row for pre-etch and 2nd row for post-etch. Five columns could be center, top,bottom, right and left. How should I do that. I have this at the moment.

  \begin{table}
    \centering
    \renewcommand{\arraystretch}{1.3}
\begin{minipage}[b]{0.33\linewidth}\centering
\caption{Measurement of oxide thickness for blank wafer before etch (pre etch)} \label{tab:1}
    \label{tab:fonts}
\begin{tabular}{|l|S[table-format=5.0,
                     table-space-text-post=\si{\angstrom}]<{\si{\angstrom}\ }|}
    \hline
center  &   5114    \\  \hline
top     &   5236    \\  \hline
right   &   5196    \\  \hline
bottom  &   5156    \\  \hline
left    &   5211    \\  \hline
\end{tabular}
\end{minipage}
\hfil
\begin{minipage}[b]{0.33\linewidth}\centering
\caption{Measurement of oxide thickness for blank wafer after etch (post etch)} \label{tab:2}
\label{tab:fonts}
\begin{tabular}{|l|S[table-format=5.0,
                     table-space-text-post=\si{\angstrom}]<{\si{\angstrom}\ }|}
    \hline
center  &   3088    \\  \hline
top     &   3154    \\  \hline
right   &   3133    \\  \hline
bottom  &   3043    \\  \hline
left    &   3112    \\ \hline
\end{tabular}
\end{minipage}
\end{table}

Answer 1

Two tables merged

\documentclass[a4paper]{article}
\usepackage[english]{babel}
\usepackage{multicol}
\usepackage{siunitx}
\begin{document}
\begin{table}
\centering
\caption{Combined result} \label{tab:etch}
\begin{tabular}{|l|S<{\si{\angstrom}\ }|S<{\si{\angstrom}\ }|}
\hline
 & \multicolumn{1}{c|}{Pre-etch} & \multicolumn{1}{c|}{Post-etch} \\ \hline   
center  &   5114    &   3088    \\  \hline
top     &   5236    &   3154    \\  \hline
right   &   5196    &   3133    \\  \hline
bottom  &   5156    &   3043    \\  \hline
left    &   5211    &   3112    \\ \hline
\end{tabular}
\end{table}
\end{document}

Three rows, five (six) columns

\documentclass[a4paper]{article}
\usepackage[english]{babel}
\usepackage{multicol}
\usepackage{siunitx}
\begin{document}
\begin{table}
\centering
\caption{Combined result} \label{tab:etch}
\begin{tabular}{|l|S<{\si{\angstrom}\ }|S<{\si{\angstrom}\ }|
S<{\si{\angstrom}\ }|S<{\si{\angstrom}\ }|S<{\si{\angstrom}\ }|}
\hline 
 & \multicolumn{1}{l|}{center} & \multicolumn{1}{l|}{top} & \multicolumn{1}{l|}{right} 
& \multicolumn{1}{l|}{bottom} & \multicolumn{1}{l|}{left} \\ \hline
Pre-etch & 5114 & 5236 & 5196 & 5156 & 5211 \\ \hline
Post-etch & 3088 & 3154 & 3133& 3043 & 3112 \\ \hline
\end{tabular}
\end{table}
\end{document}

Is this what you are looking for?

---

Explanation

I used multicol to make a multicolumn of 1 column wide to adjust the format. Alternatively you can use the tabu package as shown in this question.

Answer 2

Three columns

Personally I'd recommend the following improvements to your table:

1. Keep the data series "Pre etch" and "Post etch" in columns rather than rows, as that is easier to read. Keep "Center", "Top" etc. in the stub column to the left (first column).
2. Remove most of the horizontal lines and all vertical lines.
3. Instead of repeating the unit after each cell value, it is common to place the unit in the column heading to avoid repetition that does not add any information.

My preferred solution would be something like:

\documentclass[preview,border=5pt]{standalone}
\usepackage{siunitx}
\usepackage{booktabs} % <-- To get prettier rules in tables
\usepackage{caption} % <-- To set caption width etc.

\begin{document}

\begin{table}
  \centering
  \captionsetup{width=6cm}
  \caption{Measurement of oxide thickness for blank wafer before (pre etch) and after etch (post etch).}
  \label{tab:1}
  \begin{tabular}{l *{2}{S[table-format=4.0]}}
    \toprule
            & {Pre etch} & {Post etch} \\
            & \si{\angstrom} & \si{\angstrom} \\
    \midrule
    Center  &       5114 &        3088 \\
    Top     &       5236 &        3154 \\
    Right   &       5196 &        3133 \\
    Bottom  &       5156 &        3043 \\
    Left    &       5211 &        3112 \\
    \bottomrule
  \end{tabular}
\end{table}

\end{document}

Six columns

Although I find this layout harder to read, if this is really the layout you want, something like this might do the trick (removed most lines in this table as well):

\documentclass[preview,border=5pt]{standalone}
\usepackage{siunitx}
\usepackage{booktabs} % <-- To get prettier rules in tables
\usepackage{caption} % <-- To set caption width etc.

\begin{document}

\begin{table}
  \centering
  \captionsetup{width=9cm}
  \caption{Measurement of oxide thickness for blank wafer before (pre etch) and after etch (post etch).}
  \label{tab:1}
  \begin{tabular}{l *{5}{S[table-format=4.0]}}
    \toprule
               & {Center} & {Top} & {Right} & {Bottom} & {Left} \\
               & \si{\angstrom} & \si{\angstrom} & \si{\angstrom} & \si{\angstrom} & \si{\angstrom} \\
    \midrule
    Pre etch   &     5114 &  5236 &    5196 &     5156 &   5211 \\
    Post etch  &     3088 &  3154 &    3133 &     3043 &   3112 \\
    \bottomrule
  \end{tabular}
\end{table}

\end{document}

To avoid repetition of the unit for each column, you can write something along the lines of "All data are presented with the unit Ångström." and remove the row containing the units.