An electrical device like this requires a reverse leakage current of 500nA @ 6V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 9.1V.For operation, diode reaches 900mV @ 10mA at the maximum voltage - Forward (Vf).
BZX84C9V1_D87Z Features
reverse leakage current of 500nA @ 6V 500nA @ 6V is the maximum voltage (Tol)
BZX84C9V1_D87Z Applications
There are a lot of ON Semiconductor BZX84C9V1_D87Z applications of zener single diodes.