  A silicon-based fine granularity calorimeter is a potential technology for
the future International Linear Collider ILC, the future circular collider
CEPC, and is also the chosen technology for the upgraded CMS experiment of the
Large Hadron Collider. Active silicon sensing pads are used as MIP counters and
the standard calibration of the calorimeter uses weights based on the average
energy loss, $dEdx$. In this work, the limitations of the dEdx calibration
method in terms of energy linearity, scale and resolution are explored. In the
case of a calorimeter with varying passive layer thickness as the one planned
for CMS, the $dEdx$ method leads to a significant constant term in the
resolution function and a non-linearity of energy response. For these reasons,
a method based on the calorimeter sampling fraction that exploits the per-event
measured shower depth is presented and shown to deliver superior absolute
energy scale, linearity and resolution. Calorimetric designs in which the back
of the shower is sampled less, offer reduced cost without loss in performance.
Therefore, a proper calibration as proposed here is crucial in obtaining the
most cost- and performance-effective silicon-sampling calorimeter design.
