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Through-Glass Vias with Laser Precision LPKF Vitrion 5000
Through-Glass Vias with Laser Precision LPKF Vitrion 5000
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Glass Interposers with High-Speed Laser ProcessingIn the interconnection of highly integrated chips with conventional circuit boards, interposers are
used to compensate for different geometrical dimensions. The contacts in the tiny semiconductor
chips are converted to assembly-compatible dimensions by interposers. The new LPKF TGV process
generates highly precise holes for subsequent through-hole plating.
5000 Holes per Second Glass is an ideal substrate for integrated circuits. It is stable, has good electrical properties, possesses a compatible coefficient of thermal expansion, and is cheap. However, machining – especially on a micron scale – is tricky. Previous processes have fallen short of targets for process speed, quality, or structural resolution.
The LPKF TGV process combines the advantages of a glass substrate with the precision of a laser process. Holes could previously only be produced with insufficient quality at a maximum rate of 1 000 holes per second. But with the TGV process perfect holes can be made at five times the speed – and it’s getting faster all the time.
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An ultrashort pulse laser modifies the glass structure in a single
pulse
Each interposer has a large number of vias In a single production step, numerous interposers are produced
on a standard glass wafer
The modified holes are opened in a standard wet etching process.
The modified structures respond significantly faster to the etching
process than the unmodified glass.
The interposer connects very fine contacts from integrated
circuits to the tracks on the PCB
Metallization and structuring of the interposer
Base material is an industrial standard glass for interposers.
One single chip combines different electronic modules
Example: Circuitry on glass interposer
Overview of LPKF TGV Process
Additional Process Steps for Interposer Production
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LPKF Vitrion 5000
The LPKF Vitrion 5000 laser system is designed solely for machining delicate glass wafers. It can process panels up to 510 mm x 510 mm in size as well as max. 18” glass wafers. LPKF supplies systems for manual and automated assembly.
The LPKF Vitrion 5000 utilizes a laser that was developed specifically for these applications. System control is accomplished with user-friendly system software that enables differentiation between programming and production mode as well as integration into an MES.
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• Clean-room compatible
• Easy maintenance
• Laser safety class 1 under normal operating conditions
The LPKF Vitrion 5000 is clean-room compatible and can be easily integrated into a wall without extra requirements. All maintenance work can be performed from the back, enabling the unit to be integrated into typical semiconductor production lines. The standard version of the Vitrion 5000 is supplied with a workbench for manual handling.
Complete Solution for Interposer Production LPKF supplies not only the laser system for glass modification but also consulting services to ensure an optimum etching process.
This comprehensive package reduces inte-gration time and effort for the customer and optimizes process quality, if necessary, in collaboration with external service providers.
The camera system for precise part position detection and an integrated SMEMA interface facilitate automation of the overall interposer production process.
The laser system is installed in the gray air area and can be easily
maintained from the side or the back
The Vitrion 5000 can process machine standard wafers as well as
panels
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Process Parameters
Variable ProzessführungGlass interposers are mainly manufactured using two processes, both of which can be implemented with the LPKF TGV technology. Thus, the TGV process can be smoothly integrated into existing production chains.
In the wafer-based process, blind holes are first produced in the glass. Then the wafer is polished down to the desired glass thickness. This creates conical through-glass vias with constant taper angles and aspect ratios (hole diameter to glass thickness) of up to 1:10.
The panel-based process generates classic vias, usually in thin substrates. The laser activates the glass over the entire thickness. Subsequent etching is performed uniformly on both sides to produce the desired hourglass shape. Here, too, aspect ratios of up to 1:10 can be achieved.
In the wafer process, the laser and etching steps generate conical
blind vias in the glass. Subsequent polishing opens the holes.
The vias exhibit pinched waists. The top diameter x1 adjusts itself in
relation to the extent of material reduction.
x1
x2
X X
a a60 µm
70 µm
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Variable Hole GeometriesBoth processes can be used for glass with a thickness of up to 300 µm. Hole diameter is primarily a function of the etching time. Currently holes with diameters down to 5 µm can be made in 50-micron-thick glass in mass production operations.
• Glass as interposer
• Efficient ultrafast laser process
• Up to 5 000 holes per second
• Standard production wafers
Through control of the etching duration, the hole diameter can be adjusted precisely. The etching process reduces the overall thickness of the glass wafer by approximately 20 %.
LPK
F AG
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5399
7-03
0915
-EN
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LPKF Laser & Electronics AG sells and markets products and provides support in more than 50 countries. Find your local representative at www.lpkf.com.
Worldwide (LPKF Headquarters)
LPKF Laser & Electronics AG Osteriede 7 30827 Garbsen Germany
Phone +49 (5131) 7095-0 [email protected] www.lpkf.com
North / Central America
LPKF Laser & Electronics North America
Phone +1 (503) 454-4200 [email protected] www.lpkfusa.com
China
LPKF Tianjin Co., Ltd.
Phone +86 (22) 2378-5318 [email protected] www.lpkf.cn
Hong Kong
LPKF Laser & Electronics (Hong Kong) Ltd.
Phone +852-2545-4005 [email protected] www.lpkf.com
Japan
LPKF Laser & Electronics K.K. Japan
Phone +81 (0) 3 5439 5906 [email protected] jp.lpkf.com
South Korea
LPKF Laser & Electronics Korea Ltd.
Phone +82 (31) 689 3660 [email protected] www.lpkf.com
© LPKF Laser & Electronics AG, LPKF reserves the right to modify the specifications and other product information without giving notice. Systems and products supplied by LPKF and its subsidiaries are covered by valid or pending US and other foreign patents. Product names are only used for identification and could be trademarks or registered brand names of the companies involved.
Worldwide Support for Through-Glass Via FormationWherever they are in the world, users of LPKF systems can be supported from our application centers in Germany, the USA, Japan, Korea and China. At these centers, users have access to LPKF’s extensive experience in laser material processing.
Technical Data: LPKF Vitrion 5000Laser class 1
Max. working area (X x Y) 510 mm x 510 mm (20” x 20”)
Max. material size (X x Y)Panel: 510 mm x 510 mm (20” x 20”)Wafer: up to 18”
Data input formats DXF
Max. structuring speed > 5 000 vias/s
Pattern accuracy 0.8 + L (100”)
System dimensions (W x H x D) 1 700 mm x 1 700 mm* x 1 620 mm (67” x 67” x 63.7”)
Weight ~1 600 kg (3 527 lbs)
Operating conditions
Power supply 400 V / 16 A; 3~ + N + PE
Power Consumption 6 kVA
Cooling Water supply and return, < 22 °C (71.6 °F)
Ambient temperature 21 °C ± 0.5 °C (69.8 °F ± 1 °F)
Humidity 60 % (non-condensing)
Compressed air 0.6 MPa
Required accessories Exhaust unit
* Height incl. StatusLight = 2 100 mm (82.7”)
