BST
Gennum is a world leader in volume manufacturing of thin film BST (Barium Strontium Titanate) capacitors. Manufactured on silicon or ceramic wafers, BST capacitors offer high capacitance density, excellent high frequency performance, and exceptional tunability. Typically configured into multi-layer capacitor (MLC) arrays a customized network of capacitors having different values, properties and performance characteristics can be manufactured all on the same capacitor chip offering an unprecedented level of miniaturization, flexibility and performance.
Some BST Basics:
BST is a perovskite material with dielectric properties determined by the composition and processing parameters that are used. It can have a high dielectric constant, low-loss, or voltage tunability. Gennum has developed processes for both standard barium/strontium compositions (50/50 and 70/30) as well as expertise on how to manipulate key properties through selective processing techniques.
Depending on the application each composition has certain advantages and disadvantages:
Table 1: Measured Dielectric Properties
|
| Dielectric Property |
Composition |
| 50:50 |
70:30 |
|
| Dielectric constant |
350 |
700 |
Capacitance density
fF/square micron | 24 |
64 |
| Dissipation factor |
0.0085 |
0.012 |
| Leakage @ 3V nA/sq. cm |
9 |
36 |
Tunability of capacitance
(C @0V to C @10 V) |
< 3:1 |
6:1 |
| Breakdown voltage |
30V |
24V |
|
Gennum's BST thin films are polycrystalline resulting in minimal capacitance variation:
The high frequency performance of the BST dielectric is excellent. The high capacitance density allows for small electrode sizes, and consequently the inductances are lower than typically seen in other capacitor technologies, which allows for flat capacitances to very high frequencies:
BST capacitors can be processed to have the unique ability to change value when a voltage is applied, allowing tunable capacitors to be created:
Please
contact us regarding any questions about our BST capacitor technology and what it is capable of doing for you (see
Decoupling Capacitors,
Tunable Capacitors)
