$\Omega$	bounded circular smooth domain
d	distance between the two parallel disks
r	radial coordinate
R	radius of the device
$u\left(r\right)$	profile of the membrane
V	external electrical voltage
T	radial mechanical tension of the membrane at rest
${\lambda }^2$	parameter depending on V and T
$\delta$	parameter that weighs the fringing field effect
$\mathbf{E}$	electrostatic field
$|\mathbf{E}|$	amplitude of the electrostatic field
$K(r,u(r\left)\right)$	mean curvature
$d^{\ast }$	critical security distance
$\theta$	factor of proportionality
${ϵ}_0$	permittivity of the free space
$f_{el}$	electrostatic force
$p_{el}$	electrostatic pressure
p	mechanical pressure
$u_0$	displacement in the center of the membrane
$C_{el}$	electrostatic capacitance
$\rho$	density
h	thickness
Y	Young modulus
$\nu$	Poisson ratio
D	stiffness coefficient
$\mu (r,u(r),\lambda )$	function of proportionality
$u_1\left(r\right)$, $u_2\left(r\right)$	auxiliary functions
k	constant of proportionality between p and $p_{el}$
H	${sup}_{r\in (0,1]}|u^{\prime }\left(r\right)|$
FEM	Finite Element Method
$tol$	tolerance for Brent procedure
$TOL$	tolerance for Keller–Box Scheme
$RK$	Runge–Kutta Methods
$G(r,s)$	Green function