Interstrip capacitance of the double-sided silicon strip detector

Capacitance properties of silicon strip detectors were examined with specially designed strip patterns. Only the junction side capacitance was measured. Each capacitance of this side has a simple dependence on the strip pattern geometry. The capacitance of each sample device was measured before and after exposure to γ-rays to test the radiation hardness. It was found that the reduction of the strip width seems to be suitable for reducing the interstrip capacitance. In the case of the given desired pitch, this means that the largest gap width is preferable. The effect of the radiation exposure on the capacitance is not significantly high on the capacitance. This means that the signal-to-noise ratio should not deteriorate much during the operation. The interface of Si-SiO₂ accumulates electrons not only naturally but also by positive ion traps in SiO₂ during high-energy beam exposure. This should be the main reason for the increase of the interstrip capacitance after radiation exposure. The floating strip between the readout strip is a useful method for achieving higher resolution with smaller readout terminals