Publication | Closed Access
Polyimide Film Properties and Selective LPCVD of Tungsten on Polyimide
12
Citations
0
References
1988
Year
EngineeringTungsten Film FrontChemical EngineeringPerfect Tungsten SelectivitySelective TungstenPolymer ChemistryMaterials EngineeringMaterials SciencePolyimide Film PropertiesMaterial PropertyMaterial AnalysisHigh Temperature MaterialsPolymer ScienceApplied PhysicsSurface ScienceMaterial PerformanceThin FilmsChemical Vapor DepositionPolymer HybridElectrical Insulation
du Pont PI‐2575‐D polyimide films were characterized to determine their suitability for use as an interlevel dielectric with a selective tungsten via fill process. Polyimide films cured at 400° and 440°C were found to breakdown at voltages greater than . The pinhole density, when processed in a non‐cleanroom environment, is below 1 per cm2. The dielectric constant for 1.6 μm films is 3.9. Adhesion to thermal oxide is 100% for films in boiling water up to 1h. The maximum moisture absorption is 1.7 w/o at 90% relative humidity. Perfect tungsten selectivity was achieved in the absence of nearby tungsten surfaces at 216°C, 0.75–7.5 torr total pressure, 15:1 and times to 210 min. When the polyimide was exposed to adjacent tungsten surfaces, tungsten did deposit on the polyimide, resulting in a moving metal front. The activation energy for the rate of progress of the tungsten film front is 16 kcal/mol.