REVENUE (Details) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2022	May 31, 2021	May 31, 2020
Net sales	$ 50,829	$ 16,600	$ 22,291
Systems [Member]
Net sales	25,224	7,250	8,099
Contactors [Member]
Net sales	22,647	5,837	10,784
Services [Member]
Net sales	2,958	3,513	3,408
Wafer Level [Member]
Net sales	48,926	15,004	19,768
Test During Burn In [Member]
Net sales	$ 1,903	$ 1,596	$ 2,523