LaTeX field of columns on chip

latex_columns.tex

\documentclass{article}
\usepackage{tikz}
\usepackage{pgffor}

\begin{document}

\begin{tikzpicture}
  \draw [fill=gray!30] 
    (0,0)
      coordinate (front top left)
    -- ++(5,0)
      coordinate (source) [pos=0.5]
      coordinate (front top right)
    -- ++(0,-0.5)
      coordinate (front bottom right)
    -- ++(-5,0)
    -- cycle
  ;
  \draw [fill=gray!30]
    (front top left)
    -- ++(60:2)
    -- ++(5,0)
      coordinate (back top right)
    -- (front top right)
    -- cycle
  ;
  \draw [fill=gray!50]
    (back top right)
    -- ++(0,-0.5)
    -- (front bottom right)
    -- (front top right)
    -- cycle
  ;
  %front left corner (0.5, 0.35)
  \foreach \y/\d in {0/0,0.5/0.25,1/0.5} {
    \foreach \x in {0,1,2,3,4} {
      \draw [fill=red!70]
        (1+\x-\d,1.35-\y)
        arc [start angle=180, delta angle=180, x radius=0.25, y radius=0.15]
        -- ++(0,2)
        -- ++(-0.5,0)
          coordinate [pos=0.5] (top)
        -- cycle
      ;
      \draw [fill=red!60]
        (top) ellipse [x radius=0.25, y radius=0.15]
      ;
    }
  }
\end{tikzpicture}

\end{document}