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EXHIBIT 99.1

Press Release

For more information, contact:
Financial:	Fred Hall	Investor Relations:	Susan Pope
	Chief Financial Officer		IR Specialist
	(503) 626-7117		(503) 526-7498

For Immediate Release

IMS ANNOUNCES SECOND QUARTER 2001 RESULTS

    Beaverton, OR—July 18, 2001—Integrated Measurement Systems, Inc. (NASDAQ: IMSC) announced results for its second quarter. Net sales for the second quarter were $12.5 million, a 40% decrease from the $20.9 million reported for the second quarter of 2000. Year-to-date revenues through June 30, 2001 were $31.0 million, down 15% from the comparable period last year. Excluding expenses associated with the Company's pending merger with Credence Systems Corporation, the Company earned net income per share for the quarter of $0.00, compared with $0.42 for the second quarter of 2000. For the year-to-date, net income per share, excluding merger related expenses, was $0.22, compared with $0.65 before the cumulative effect of an accounting change for the comparable period in 2000. Including the impact of merger related expenses, the Company incurred a net loss per share for the quarter of $0.11 and earned net income per share of $0.11 for the year-to-date.

"We expected this quarter to be difficult and it proved to be even more so than we had estimated," said Keith Barnes, President and Chief Executive Officer. "Toward the end of last quarter, we became concerned about the impact the current industry downturn was having on our business. We took steps at that time to lower our expense run rate and as a result, we were able to break even excluding merger related expenses during this very difficult selling quarter. These steps, along with attention to cash collections, also had a positive impact on cash flow as we increased our cash balances by $1.5 million during a soft revenue quarter."

Mr. Barnes added, "There were other positives during the quarter as well. We sold our first Vanguard 550, mixed signal revenues were a very solid $4.7 million and our memory system sales at $2.2 million were the highest yet for that product. Additionally, the pending merger with Credence continues to move along well on both the legal and integration planning fronts. Although the short term visibility continues to be murky, we feel confident that we are well positioned to take advantage of the anticipated industry upturn when it occurs."

    The Company will hold a conference call tomorrow, July 19, 2001, at 8:30 a.m. Pacific Daylight Time. The session will include brief remarks and a question and answer period. The call can be accessed by calling 800-834-5966 (confirmation number 19252179) or via live audio webcast at either www.ims.com (Investor Relations) or www.streetfusion.com. A replay will be available at www.ims.com (Investor Relations).

    Except for the historical information herein, the statements contained in this release are forward-looking statements within the meaning of the Securities Litigation Reform Act of 1995 which are based on current expectations, estimates and projections about the Company's business, management's beliefs, and assumptions made by management. These statements are not guarantees of future performance and involve risks and uncertainties that are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed or forecasted in such forward-looking statements due to numerous factors, including the cyclical nature of the semiconductor industry, changes in demand for

the Company's products, product mix, the timing of customer orders and deliveries, the timing of customer acceptances, high concentration of revenue from a single customer, a disproportionate amount of orders booked toward the end of any quarter, the impact of competitive products and pricing, constraints on supplies of critical components, excess or shortage of production capacity, actual purchases under agreements, difficulties encountered in the integration of acquired businesses and other risks discussed from time to time in the Company's Securities and Exchange Commission filings and reports. In addition, such statements could be affected by general industry and market conditions and growth rates, and general domestic and international economic conditions. Such forward-looking statements speak only as of the date on which they are made and the Company does not undertake any obligation to update any forward-looking statement to reflect events or circumstances after the date of this release.

    IMS designs, manufactures, markets and services a family of versatile, high-performance engineering validation systems used to verify and characterize complex electronic devices. In addition, the Company develops and markets a line of Virtual Test™ Software products that allow IC test development and simulation before first-silicon.

    For additional company information, see the IMS Web sites at www.ims.com and www.imsvirtualtest.com.

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Integrated Measurement Systems, Inc.
Consolidated Statements of Operations
(In thousands, except per share amounts)
(Unaudited)

			Three Months Ended June 30,					Six Months Ended June 30,
			2001			2000		2001			2000
Revenues
	Systems		$	9,000		$	16,794	$	22,623		$	28,396
	Software			917			1,524		3,256			3,252
	Service			2,548			2,543		5,107			4,956
		Net revenues		12,465			20,861		30,986			36,604
Cost of Revenues
	Systems			3,990			6,376		9,488			11,035
	Software			248			274		567			623
	Service			1,017			1,121		2,149			2,188
		Total cost of revenues		5,255			7,771		12,204			13,846
		Gross margin		7,210			13,090		18,782			22,758
Operating Expenses
	Research, development and engineering			2,658			2,447		5,185			4,453
	Selling, general and administrative			5,028			5,695		11,585			10,633
	Merger expenses			1,375			—		1,375			—
		Total operating expenses		9,061			8,142		18,145			15,086
		Operating income (loss)		(1,851	)		4,948		637			7,672
Interest income				452			366		976			674
Other expense, net				40			81		(124	)		58
Income (loss) before provision for income taxes and cumulative effect of accounting change				(1,359	)		5,395		1,489			8,404
Provision for (benefit from) income taxes				(462	)		1,834		506			2,857
Income (loss) before cumulative effect of accounting change				(897	)		3,561		983			5,547
Cumulative effect of accounting change				—			—		—			(7,317	)
		Net income (loss)	$	(897	)	$	3,561	$	983		$	(1,770	)
Basic earnings (loss) per share:
	Income before cumulative effect of accounting change		$	(0.11	)	$	0.45	$	0.12		$	0.71
	Cumulative effect of accounting change			—			—		—			(0.94	)
	Net income (loss)			(0.11	)	$	0.45		0.12		$	(0.23	)
Diluted earnings (loss) per share:
	Income before cumulative effect of accounting change		$	(0.11	)	$	0.42	$	0.11		$	0.65
	Cumulative effect of accounting change			—			—		—			(0.85	)
	Net income (loss)		$	(0.11	)	$	0.42	$	0.11		$	(0.20	)
Shares used for basic earnings per share				7,904			7,828		7,905			7,774
Shares used for diluted earnings per share				7,904			8,529		8,520			8,579

Integrated Measurement Systems,Inc.
Consolidated Balance Sheets
(Dollars in thousands, except share data)

			As of June 30, 2001		As of December 31, 2000
			(Unaudited)
ASSETS
Current Assets:
	Cash and cash equivalents		$	6,499	$	18,312
	Short-term investments			32,003		23,215
	Trade receivables, less allowance for doubtful accounts of $318 and $376			7,585		11,480
	Inventories, net			12,921		10,984
	Inventories at customer sites			621		2,937
	Deferred income taxes			3,808		3,808
	Income taxes receivable			—		1,247
	Prepaid expenses and other current assets			4,133		4,425
		Total current assets		67,570		76,408
Property, Plant and Equipment, net				10,190		10,121
Service Spare Parts, net				3,410		3,125
Software Development Costs, net				3,183		3,519
Other Assets, net				230		427
		Total assets	$	84,583	$	93,600
LIABILITIES AND SHAREHOLDERS' EQUITY
Current Liabilities:
	Accounts payable		$	2,045	$	2,280
	Payable to Cadence, net			429		92
	Accrued compensation			1,543		2,076
	Accrued warranty			1,016		1,290
	Deferred systems revenue			1,683		10,603
	Other deferred revenue			3,153		3,103
	Other current liabilities			1,866		2,293
	Income taxes payable			186		—
	Capital lease obligations—current			135		213
		Total current liabilities		12,056		21,950
Deferred Income Taxes				1,357		1,357
Deferred Compensation				1,828		1,772
Shareholders' Equity:
	Preferred stock, $0.01 par value, 10,000,000 shares authorized; none issued and outstanding			—		—
	Common stock, $0.01 par value, 15,000,000 shares authorized; 7,950,020 and 7,935,320 shares issued and outstanding			79		79
	Additional paid-in capital			45,709		45,871
	Retained earnings			23,554		22,571
		Total shareholders' equity		69,342		68,521
		Total liabilities and shareholders' equity	$	84,583	$	93,600

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IMS ANNOUNCES SECOND QUARTER 2001 RESULTS
Integrated Measurement Systems, Inc. Consolidated Statements of Operations (In thousands, except per share amounts) (Unaudited)
Integrated Measurement Systems,Inc. Consolidated Balance Sheets (Dollars in thousands, except share data)