R-shunt of photodiode

[foollikeafox]

I have a tester to measure the R-shunt of the photo-diode array.
recently, i found some diode array can't pass the test, because the R-shunt exceed the limit scope as the following test result.
Can someone know the possibility? ESD or mechanical damage or others?

forward test data: 3.26555e+10
reverse test data :1.02546e+06
average data: 1.63283e+10
lower: 3.71e+08
upper: 1.25e+09
:?:

 

[D.A.(Tony)Stewart]

exceeding the rated voltage to measure leakage can cause induce faults as well as similar voltage ESD.

Measuring to 5 decimal places seems ludicrous.

PD arrays have a dark current due to background radiation and noise.