Skip to main content

THIN-FILM TECHNOLOGIES

Production of the finest structures

We produce microwave integrated circuits (MIC) and modules using gold-based thin-film technology. Based on ceramic substrates and taking into consideration the highest requirements for precision and quality, we are in a position to be able to produce future-oriented thin-film products. Not only do we manufacture customer-specific thin-film circuits, we also advise our customers about new technologies and solutions. Just send us your product inquiry!

 

 

We offer the following services:

  • Production of prototypes, small series and series production

Our services include:

  • Customer consulting for new solutions and technologies
  • Checking of layouts by our engineers according to our design regulations
  • CAD services
  • Optimization of layouts to increase your profitability

 

 

Substrate materials


  • Substrates are used as the basis for the circuit board and resistance layers
  • MIC (Microwave Integrated Circuits) are realized based on:
  • aluminum oxide (Al2O3), aluminum nitride (AlN), ferrite and quartz glass

 

 

SubstratesSurfacesDielectric constant @ 1MHz eᵣ7 mil10 mil15 mil20 mil25 mil40 milLaser cuttingLaser drillingSawing
Aluminium oxide 99.6% (Al₂O₃)as fired9.8-10.1XXXXXXXX
Aliminium oxide 99.6% (Al₂O₃)polish9.8-10.1XXXXXXXX
Aluminium oxide 99.6% (Al₂O₃)TPS polish10.1-10.2XXXXXXXX
Aluminium nitride (AIN)as fired8.8XXXXXXXX
Aluminium nitride (AIN)polish8.8XXXXXXXX
Aluminium nitride (AIN)8.8XXXXXXXX
Quartz glass
(Si O₂)
polish3.8XX
Ferrit substratepolish
(Ra=0.3)
13.1-15.0XXXXXX

 

Typical tile sizes for Al2O3 and AlN are 2” x 2”, 2.5” x 2.5” and 4” x 4” and for ferrite substrates 2” x 2”.

Additional materials are available upon request. The availability and qualification for the thin-film processing are a pre-requisite.

 

 

Layer system

Die Strukturierung des MIC-Substrates ist halbadditiv. Zuerst wird das Substrat mit einer  Widerstandschicht (TaN), der Haftschicht (TaN) und einer dünnen Gold-Leiterschicht mittels Sputtern, einem Vakuumbeschichtungverfahren, versehen. Anschließend wird ein Fotolack aufgebracht und mit fotolithographischen Verfahren strukturiert. Die Au-Leitschicht wird galvansich auf die gewünschte Dicke verstärkt. Nach dem Entfernen des Fotolacks wird die endgültige Leiterbahnstruktur freigeätzt. Die Wahl des eigentlichen Schichtaufbaus hängt dabei von verschiedenen Faktoren ab, z.B. der geforderten Leitfähigkeit der Leitschicht, der Integration von Widerständen, der späteren Montagetechnik und den Umgebungsbedingungen beim Einsatz der Schaltung ab.

Für die Realisierung lötbarer Schaltungen bieten wir zusätzlich zur konventionellen bondbaren Gold Technologie zusätzlich einen ENIG-Prozess an, der eine zusätzliche partielle chemische Ni-Au-Beschichtung auf der Oberfläche vorsieht.

The AFT layer system

LayerMaterialNominal thickness [µm]Thickness tolerance [µm]
Galvanic layer

AU

Ni

<1

4

 

± 2

Sputtered layerAU

3

5

10

± 1

± 1

± 2

Sputtered layerAU0,3
Adhesive layerTiW0,14
Resistor layerTaN

 

For both layer structures, the TaN resistor layer can be realized with a sheet resistance R□ of 20 Ω, 50 Ω or 100 Ω with a tolerance of 0% / -30%. Depending on the circuit, a laser compensation of the resistors to ±1% is possible.

In specialized cases, sheet resistance of 42 Ω or 50 Ω with ±10% tolerance without compensation can be realized.

The significant design guidelines

The most important design guidelines for circuit paths, resistors, through-hole plating and air bridges.

The following requirements apply for the circuit board widths and gap widths:

 

Circuit pathsThickness circuit path metallizationMin. circuit path/gap widthwidth toleranceMin. circuit path/gap width* special requestMin. circuit path/gap width* special request
Gold (Au)3 μm20 μm± 3 μm10 μm± 2 μm
5 – 10 μm50 μm± 5 μm----

* not in combination with through-hole plating

As a feature of thin-film circuit boards, we also offer:

  • PI capacitors
  • PI bridges
  • Air bridges

Realization of PI capacitors and PI bridges

 

                                                         Thickness PI [µm]Thickness tolerance [µm]Min. structure widths
Capacitor and PI bridges4 μm-2 / +120 μm

Realization of air bridges

 

Air bridgesDimensions
Width of the bridge≥ 20 μm
Height of the bridge5 – 10 μm
Diameter of pillar≥ 20 μm

 

 

Laser processing and sawing

Computer-controlled laser processing:

  • Lasers of varying contours and cross-sections
  • Laser boreholes with the smallest diameters of 0.150 μm for electrical through-hole plating
  • Separation of circuit boards via laser scribing
  • Separation of circuit boards with a wafer saw for substrates up to 4” x 4” and 1 mm thickness