vertical transistor
A transistor with source, gate and drain stacked on top of each other. More vertical transistors can fit on a chip than the traditional horizontal architecture. Not only are the rearranged elements automatically space saving, but the dummy isolation gates between transistors used on the common horizontal layout are no longer needed. Intel, IBM and Samsung are developers of vertical transistors. See gate pitch, chip manufacturing, transistor and FinFET.
Vertical vs. Horizontal
The vertical orientation (top) obviously saves space compared to the traditional horizontal arrangement of the transistor's elements.