Does tiptronic transmission always use clutches or dual cluctch packs? Or are they also built on CVT or other automatic transmission technologies?
"Tiptronic" is a term that has both a general meaning and a specific one.
Specifically it refers to the Porsche system that allows the driver to up and down shift in a conventional automatic gearbox. So a "true" Tiptronic 'box is a torque-converter automatic with a driver-controlled up and down shift override, by means of steering wheel mounted buttons/paddles, a second operating plane on the shift gate (with spring-loaded "upshift" and "downshift" positions) or both.
While Porsche own the trademark they license it for use by other manufacturers to describe their own systems that provide similar functionality. As a result it has come to be a general term referring to any automatic transmission that allows for manually controlled up and down shift.
In this general use of the term the underlying gearbox technology itself is fairly independent, it's the control interface that is presented to the driver - it can be a conventional torque-converter auto (such as the ZF 5HP24A), a dual-clutch automatic (such as the BorgWarner DSG unit used by VW/Audi), a CVT that simulates the "gears", or anything really.