22pF 50V Bordered Single Layer Capacitor Platinum Barrier Capacitor For High Frequency

High-Frequency Technical Summary
   The HACC220S15V500 is an ultra-miniature, high-frequency Single-Sided Bordered Single Layer Ceramic Capacitor (SLC). This model is engineered specifically for broadband DC blocking, RF coupling, and microwave tuning in the millimeter-wave spectrum up to 40.0 GHz (covering S, C, X, Ku, K, and Ka-band hybrid microcircuits). Delivering an ultra-low 22 pF ± 10% capacitance and rated for a continuous working voltage of 50 V, it is packed into an incredibly compact 15 mil × 15 mil (0.38 mm × 0.38 mm) outline with a ultra-low profile height of 0.15 mm.

   Designed with a single-sided bordered structure, the top gold electrode has a clean insulating ceramic margin. This border prevents conductive epoxy climb-up or solder bleed-out from short-circuiting the device. The bottom electrode features a fully metallized, solder leach-resistant TiW-Pt-Au structure, making it highly compatible with both silver epoxies and high-temperature eutectic solders.

Key Performance Advantages
   Broadband Millimeter-Wave Coupling (0.8 - 40.0 GHz): Due to its ultra-low capacitance (22 pF) and microscopic size, it exhibits exceptionally low insertion loss and high self-resonant frequency (SRF), behaving as a near-perfect transmission element.
   Insulating Margin Prevention: The single-sided ceramic border acts as a physical dam to stop conductive silver epoxy from climbing onto the top electrode, ensuring reliable, short-free die attachment.
   Asymmetrical Metallization (Pt Solder Barrier): Top contact has TiW-Au (2.5 µm Min) for gold wire thermosonic bonding. Bottom has TiW-Pt-Au (2.5 µm Min) where the Platinum (Pt) layer acts as a premium barrier against gold scavenging/leaching.
  Ultra-Low Profile Height: At only 0.15 mm, it sits perfectly flat inside microscopic RF cavities, minimizing parasitic inductance.

Overall Dimensions

Comprehensive Parameter Datasheet

Thin-Film Metallization Stack Engineering
To ensure reliable wire bonding on the top and prevent solder scavenging on the bottom, the HACC220S15V500utilizes a high-reliability thin-film metallization system:

S-Parameter Engineering & Sub-Millimeter Assembly Guide
To maximize high-frequency coupling and bypass efficiency while preventing mechanical damage, assembly engineers must adhere to the following guidelines:

Epotek H20E Conductive Silver Epoxy SOP
   Adhesive Specification: Use high-reliability, low-outgassing conductive silver epoxy (e.g., Epotek H20E).
   Dispensing Guidelines: Apply a microscopic dot of epoxy. Thanks to the top ceramic border on the HACC220S15V500, the epoxy is physically prevented from bridging to the top contact.
   Thermal Cure Profile: Cure at 120°C for 30 minutes (or alternatively 150°C for 15 minutes) with a slow-ramp cool-down to eliminate thermal shock on the ceramic substrate.

Gold Wire & Ribbon Bonding Constraints
   Bonding Method: Compatible with thermosonic gold wire bonding (ball-stitch or wedge-wedge) and gold ribbon bonding.
   Safe Bonding Clearance: The bonding wedge or capillary tip must land on the top gold pad at least 25 µm away from the electrode border edge. Bonding too close to the ceramic border will cause localized shearing forces, risking gold peeling or micro-cracks in the dielectric.
   Bonding Force: Control capillary pressure to prevent micro-fracturing the thin 0.15 mm ceramic wafer.

FAQ
Q1: What is the benefit of the TiW-Pt-Au bottom metallization on the HACC220S15V500?
  A:During gold wire bonding or high-temperature solder reflow, standard gold-plated electrodes can suffer from "gold scavenging," where the gold dissolves or migrates into the mounting medium, weakening the bond. The bottom of the HACC220S15V500 features a sputtered Platinum (Pt) barrier layer between the TiW base and the Au finish. Platinum acts as a highly effective diffusion block that does not dissolve in solders, ensuring absolute mechanical adhesion and a highly reliable low-resistance connection.

Q2: Why is the HACC220S15V500 highly recommended for millimeter-wave bands up to 40 GHz?
  A:In the millimeter-wave spectrum (e.g., K-band, Ka-band), parasitic inductance and resistance must be minimized. Multi-layer capacitors (MLCCs) have relatively high parasitic inductance (ESL) due to their multi-electrode structure, which leads to self-resonance at lower frequencies. The HACC220S15V500 is a single-layer capacitor with an ultra-short coaxial-like path, yielding exceptionally low ESL and ESR. With a tiny 22 pF capacity and a microscopic 15 mil footprint, its self-resonant frequency is extremely high, allowing it to behave as an almost ideal transmission element up to 40 GHz.

Q3: Why does this model use a single-sided bordered design instead of a double-sided bordered design?
   A:The single-sided bordered design is optimized for maximum ground contact area. By keeping the bottom electrode fully metallized (borderless), the capacitor achieves a larger bonding contact area on the substrate housing. This maximizes electrical ground contact, yielding the lowest possible RF impedance and excellent thermal heat transfer, while the top bordered electrode still provides 100% protection against short-circuits.