Chuck Design

Chuck Design.

Solutions for High-Performance Applications.

Berliner Glas develops innovative chuck solutions for the most diverse and demanding processing steps in the semiconductor industry.

Vacuum Chucks
Electrostatic Chucks (ESCs)

For more information about our approach, our expertise and our new test center to shorten development cycles please click here.

Chucks for wafers up to 450 mm (18 inch)
Chucks for reticles
Customer-specific formats up to 400 x 500 mm²
Single or double-sided clamps
Exact temperatures up to small mK
Integrated heating and cooling functions (options)
Hybrid chucks (ESC & vacuum chuck combined)
Wide range of functional surface coatings

Chuck design (ESC) with features

ESC specific:

Coulomb type with up to 8 electrodes per side
Single or multi-polar electrodes (mono- and bipolar systems)

Vacuum chuck specific:

Up to 4 separate vacuum segments
Supports both rotating as well as lateral platforms

Flatness

Global flatness up to 100 nm PV (D=298 mm)
Local flatness us to 10 nm PV (20x20 mm²)
Specific flatness needs according to application possible

Global flatness < 100nm to 298mm

Shape Control

Absorption of warped wafers
Flatten warped wafers
Controlled adjustment of wafer shapes

Clamping Pressure

Homogeneous clamping force over the entire clamp surface

Up to 0.5 bar of clamping pressure for ESCs and up to 1 bar for vacuum chucks
Time constants to hold and release smaller than 0.1 seconds

Material

Metal	Aluminium with coating
Ceramics	SiC, SiSiC AlN, Si₃N₄ Al₂O₃ Cordierit
Glass & Glassceramics	Borosilicate Glass Quartz Glass ULE^®, Zerodur^®

Metal	Ceramics	Glass & Glassceramics
Aluminium with coating	SiC, SiSiC AlN, Si₃N₄ Al₂O₃ Cordierit	Borosilicate Glass Quartz Glass ULE^®, Zerodur^®

Chuck materials with silicon-adapted properties
Materials with "zero expansion"
Materials with high stiffness
Materials with high thermal conductivity and abrasion resistance
Combination of various materials to ensure the highest performance
All materials satisfy the semiconductor standard

Electrostatic chuck with integrated cooling

Electrostatic chuck made from glass and ceramic

Microstructure

Pin structures reduce the contact surface of the wafer to the chuck by a factor of 100 (1 % of contact surface)

No sticking between wafer and chuck
Very low particle sensitivity
Pin size up to 300 µm in diameter

Pin structure of an electrostatic chuck

Testing & Qualification

In our laboratory, we qualify test parts as well as measurement and reference parts and conduct test series in order to guarantee successful volume production.

Possible qualifications:

Flatness measurement using interferometer (up to 24 inches horizontal and 12 inches vertical beam path)
Customer-specific software for a very accurate evaluation of flatness
Electrical qualification in an application-oriented environment (high voltage test)
Measurement of clamping force
Residual gas analysis (RGA)
Backside contamination analyses
Flow-through tests for coolants and gas