DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Jun. 30, 2020

Accounting Policies [Abstract]

Property, Plant and Equipment

The following table sets forth the estimated useful life for various asset categories:

Asset Category	Range of Useful Lives
Buildings	30 to 50 years
Leasehold improvements	Shorter of 15 years or lease term
Machinery and equipment	2 to 10 years
Office furniture and fixtures	7 years

Schedules of Concentration of Risk

The following customers each accounted for more than 10% of total revenues primarily in Semiconductor Process Control segment for the indicated periods:

Year ended June 30,
2020	2019	2018
Taiwan Semiconductor Manufacturing Company Limited	Taiwan Semiconductor Manufacturing Company Limited	Samsung Electronics Co., Ltd.
Samsung Electronics Co., Ltd.

The following customers each accounted for more than 10% of net accounts receivable as of the dates indicated below:

As of June 30,
2020	2019
Taiwan Semiconductor Manufacturing Company Limited	Taiwan Semiconductor Manufacturing Company Limited
Samsung Electronics Co., Ltd.