The Q-Hall technology was patented in 2003. It uses four Hall plates in a Quad configuration. The currents in the Hall plate are rotated in a pre-determined way in order to compensate for offsets induced by (shear) stresses, temperature gradients and self-induced magnetic fields.
These offset compensation techniques lead to unprecedented accuracy for silicon Hall plates. The production spread in offset is about one microtesla, while the stability is even better.