Are super computers made with just cache technology?

Perhaps its a misunderstanding that supercomputers are primarily about speed, because that's not necessarily the case.

Supercomputers are about computing, about power. Dealing with very large sets of data containing very large or very complex values very quickly. This doesn't require speed so much as power: super-wide buses, huge instruction sets, and the ability to send huge amounts of data around to various places pretty quickly.

That last part is the only part where "speed" as we generally conceive of it really comes in and it's generally dealt with by using superfast networking, because most supercomputers are just too large for information to be shuttled between components by pathways etched in silicone.

I suppose it may be easy to misunderstand this as well. Super computers are definitely fast. Faster than anything Alienware and $10k can get you. But most of their ability, the power, comes not from speed so much as that ability, previously stated, to do complex things with huge chunks of data all at once.