  The extension of piezoresistance coefficient extraction method was proposed,
for protection from errors in estimation of the thickness of the test structure
membrane. This new approach requires finding models of elements of matrix of
integrated stresses as functions of the membrane thickness. Additionally, two
test structures with different thickness of the membrane have to be used. This
improved method gives the more credible estimation of piezoresistance
coefficients $\pi_L$ and $\pi_T$ and the thickness of the membranes of the used
test structures.
