Vacuum News

The FSU 010 programmable freeze substitution unit from Balzers

features a newly developed method of SEM specimen preparation, in

contrast to conventional methods of dehydration and chemical

fixation.

In contrast to conventional methods of dehydration and chemical

fixation, specimens are first freeze fixed by well known fast freezing

methods. Dehydration and substitution, using acetone, methanol

etc., take place in three separate stages, starting at approximately -90°C

and progressing with each stage to -3O’C.

The temperature and duration of each freezing step (O-999 h) can

be pre-programmed, and on completion the frozen tissues are fixed

with Lowicryl. Subsequent uv polymerisation, at low and room

temperature is also possible with this unit.

Additional features include an LCD display panel for the different

process temperatures and a standard specimen holder for substitution

and uv polymerisation.

More information can be obtained from :

Alan Bussell

Balzers High Vacuum Ltd

Northbridge Road, Berkhamsted, Herts HP4 1 EN

Tel 04427 2181

Telex 82209 VACUUM G

Computerised gas analysis from Bakers advances IC quality control

An inclusion piercing system, developed by Balzers from known

computer controlled mass spectrometry techniques, represents a

significant step in fast, accurate quality control for integrated circuit

production.

Based around a Balzers QMG 511 quadrupole mass spectrometer,

the GIA707 system is designed for the failure analysis of hermetically

sealed IC packages and the identification of minute gas inclusions,

or bubbles, often found in IC packaging materials, such as minerals,

plastics and glass.

The system is an adaption of the well established method of

computer aided gas analysis of sealed electronic devices in general. As

well as the quadrupole it includes a number of other items from

Balzers’ mass spectrometry equipment range, supported by an

interactive software package, that can now apply the same principle

to identify gas inclusions in materials down to volumes of lo-” atm I

and below.

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Close up of the G/A707 system viewing chamber, with the sealed

piercing ram visible through the sight glass. The Balzers G/A707 is

designed for the failure analysis of hermetically sealed IC packages

and the identification of gas inclusions often found in IC packaging

materials.

It is currently estimated that a substantial percentage of integrated

circuit failures are related to contamination problems in the package

caused by moisture, leaks and gases held in inclusions.

It is the availability of the computer software packages used in the

new Balzers system that now offers the qualitative and quantitative gas

analysis necessary to provide rapid identification of the exact cause,

thereby enabling much tighter quality control.

The GIA707 is comprised of four basic units, namely the quadrupole

mass spectrometer, a sample chamber with a bellows-sealed piercing

device, a calibration unit (optional), and a data system with printer

and software package.

In practise, samples are introduced to a small vacuum chamber,

which is equilibrated at a predetermined temperature and then pumped

down to a suitable background pressure. When this is reached a

valve is opened to the quadrupole mass spectrometer and the

background contributions are determined. The sample is pierced in

situ and the escaping gas analysed.

To aid practical operation Balzers has arranged the system as a well

planned work station, with positions allocated for optional units, such

as a video terminal, and leaving sufficient space for calibration gas

bottles.

More information can be obtained from :

Neil Henderson

Balzers High Vacuum Ltd

Northbridge Road, Berkhamsted, Herts HP4 1 EN Tel 04427 2181

Telex 82209 VACUUM G

Fax 04427 7172 7