Organization and Significant Accounting Policies (Tables)

3 Months Ended

Mar. 28, 2014

Accounting Policies [Abstract]

Customers as Percentage of Total Sales

Sales to each of these customers as a percentage of total sales were as follows:

	Three months ended
	March 28, 2014			March 29, 2013
Lam Research Corporation		34.3	%		28.6	%
Applied Materials, Inc.		25.3	%		36.9	%
ASM International		19.4	%		12.3	%
Intuitive Surgical, Inc.		*	%		10.6	%
Total		79.0	%		88.4	%

*Sales to this customer were less than 10% for the three months ended March 28, 2014.

Financial Assets and Liabilities Measured at Fair Value

Financial assets and liabilities measured at fair value are summarized below (in thousands):

	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs
	March 28, 2014				December 27, 2013
	(level 1)		(level 2)		(level 1)		(level 2)
Money market fund deposits (1)	$	10,043		—	$	13,414		—

(1) Included in cash and cash equivalents on the condensed consolidated balance sheet. The carrying amounts approximate fair value due to the short-term maturities of the cash equivalents.

Components of Reserve for Warranty Costs

Components of the reserve for warranty costs consisted of the following (in thousands):

	Three months ended
	March 28, 2014			March 29, 2013
Beginning balance	$	101		$	152
Change in reserve		67			(17	)
Warranty costs incurred in the current period		(57	)		(20	)
Ending balance	$	111		$	115

Stock Option Activity

Stock option activity for the three months ended March 28, 2014:

	Number of Shares			Weighted Average Exercise  Price		Weighted  Average Remaining Contractual Term (years)		Aggregate  Intrinsic Value (in thousands)
Outstanding at December 27, 2013		1,209,119		$	7.86		2.86	$	3,976
Granted		—			—
Exercised		(337,997	)	$	5.13
Canceled		(1,846	)	$	13.42
Outstanding at March 28, 2014		869,276		$	8.91		2.43	$	3,701
Options exercisable and expected to vest at March 28, 2014		869,276		$	8.91		2.43	$	3,701

Restricted Stock Unit and Restricted Stock Award Activity

The following table summarizes the Company’s restricted stock unit and restricted stock award activity for the three months March 28, 2014:

	Number of Shares			Aggregate  Intrinsic Value (in thousands)
Unvested restricted stock units and restricted stock awards at December 27, 2013		1,256,930		$	12,632
Granted		464,500
Vested		(407,243	)
Forfeited		(247,522	)
Unvested restricted stock units and restricted stock awards at March 28, 2014		1,066,665		$	12,927
Vested and expected to vest restricted stock units and restricted stock awards at March 28, 2014		871,359		$	10,866

Stock-Based Compensation Expense Included in Condensed Consolidated Statements of Operations

The following table shows the Company’s stock-based compensation expense included in the condensed consolidated statements of operations (in thousands):

	Three months ended
	March 28, 2014			March 29, 2013
Cost of sales (1)	$	326		$	417
Research and development		71			88
Sales and marketing		132			132
General and administrative		490			683
		1,019			1,320
Income tax benefit		(176	)		(223	)
Total stock-based compensation expense, net of income tax benefit	$	843		$	1,097

(1) Stock-based compensation expenses capitalized in inventory for fiscal quarter March 28, 2014 and March 29, 2013 were considered immaterial.