HERMETIC SEAL TESTING
OF MICROELECTRONIC & SEMICONDUCTOR DEVICES
USED IN MILITARY, AEROSPACE, AUTOMOTIVE AND
COMMERICIAL APPLICATIONS

Purpose:

To test the effectiveness (hermeticity) of the seal of metal and ceramic devices with designed internal cavities. A leaky seal is likely to allow the component to fill with unwanted contaminates from the air and cause premature failure.

ADVANTAGES OF HERMETIC SEAL TESTING OF YOUR COMPONENTS

1.	Detection of leaking packages allows you to find and fix the manufacturing process problem... before it's too late.
2.	You can significantly increase your potential customer base by certifying that your product has passed Fine and Gross Leak Testing.

InterTest offers cost effective solutions to hermetic seal testing. In fact, besides ease of operation, maintenance and calibration, InterTest products exceed Mil-Std-883 requirements, as well as less stringent requirements of Mil-750, Mil-202 and commercial equivalents!

FINE LEAK SEAL TESTING- HERE'S HOW IT WORKS

Fine Leak Testing is accomplished by a two-part process:

Part 1: Fine Leak Preconditioning

Preconditioning with an InterTest Model 1014-CII Fine/Gross Pressurization System- This unit performs the following process:

A.	Parts are placed in one of the preconditioning chambers.
B.	A vacuum is pulled on the chamber.
C.	The chamber is pressurized up to 90 PSIA with helium.
D.	Pressure is maintained for the prescribed time. (Usually 2 hours)
E.	The pressure is automatically vented.
F.	The parts are ready to be Helium Leak Tested in a Helium Leak Detector.

Part 2: Fine Leak Testing

Helium Fine Leak Testing is accomplished with a Helium Mass Spectrometer (manufactured by Varian). Failed parts are determined by the following procedure:

A.	Parts are placed in the test chamber (after preconditioning).
B.	The test button initiates the actual test.
C.	If helium is detected which exceeds the preset leak rate set point, an alarm alerts the operator of a fine leak failure.

GROSS LEAK SEAL TESTING- HERE'S HOW IT WORKS

Gross Leak Testing is accomplished by a two-part process:

Part 1: Gross Leak Preconditioning

Preconditioning with the same InterTest Model 1014-CII Fine/Gross Pressurization System- This unit performs the following process:

A.	Parts are placed in one of the preconditioning chambers.
B.	A vacuum is pulled on the chamber to 5.0 mm..Hg.
C.	Vacuum is maintained for the prescribed time (Usually 30-60 Minutes).
D.	Fluorocarbon fluid (3M FC-84™) is pumped into the chamber to cover all the parts.
E.	The chamber is pressurized up to 90 PSIA with nitrogen.
F.	Pressure is maintained for the prescribed time. (Usually 2 hours)
G.	The pressure is automatically vented, and the fluid is drained.
H.	The parts are now ready to be Gross Leak Tested in an InterTest Bubble Detection System.

Part 2: Gross Leak Testing

Gross Leak Detection is accomplished with an InterTest Model 1014-CBL Bubble Detection System. Failed parts are determined by the following procedure:

A.	Parts are placed on a dipping basket, then submerged in the observation tank of the InterTest Bubble Detection System. The tank contains a heated bath of fluorocarbon fluid (3M FC-40™) at 125°C. The fluid is brightly illuminated and magnified which improves the operator's visibility.
B.	The operator views the parts for a period of 30-60 seconds.
C.	A part that fails this Gross leak test is detected by its emission of two large bubbles or a steady stream of bubbles from a single point on the package.

Gross Leak Test Theory:

In Step 1, FC-84™ is forced into the "bad" package. FC-84™ boils at approximately 80° C, and has a density of 14.3 lbs./gallon. In Step 2, FC-40™ is heated to 125° C. FC-40™ boils at approximately 200° C, and has a density of 15 lbs./gallon. When a part containing FC-84™ is placed in the FC-40™ at 125°C, the FC-84™ boils, expands and forces its way out of the part at the bad seal or leak. It is visibly detected by a stream of bubbles that rise from the part to the top of the FC-40™ bath.

Recommended Equipment for Fine and Gross Leak Testing:

MIL-STD-883, 750, 202 & OTHERS

METHOD	TEST CONDITION	PRECONDITIONING EQUIPMENT	LEAK TEST EQUIPMENT	DETECTS LEAK PATHS (CRACKS OR HOLES) WHICH PRODUCE A LEAK RATE OF:
1014	A = FINE	InterTest Model 1014-CII Fine/Gross Preconditioning System	Varian Model 947 Helium-Mass Spectrometer	5 X 10-8 ATM cc/s
1014	C = GROSS	InterTest Model 1014-CII Fine/Gross Preconditioning System	InterTest Model 1014-CBL Bubble Detection System	Two Large Bubbles or a Continuous Stream of Bubbles

For additional technical assistance, or for product information, contact the InterTest Equipment Services factory.

Phone:		(408)298-7747
Email:		service@intertest.cc
Fax:		(408)298-7787