Low Dissipation Factor 50pF 50V MOS Capacitor Custom Metal Metallization SLC Chip for RF Power Packaging

HACC500S50V500 Custom Low Dissipation Factor MOS Capacitor 50pF 50V Minimal Tan δ Under RF Power — Fully Customizable Metal Layout & Geometry

The HACC500S50V500 is a fully customizable 50 pF 50 V single-layer MOS capacitor featuring industry-leading low dissipation factor (tan δ < 0.001 at 1 GHz) verified under full RF power excitation up to +40 dBm (10 W) continuous wave. With a fully configurable metal layout—including selective gold thickness, patterned multi-pad electrodes, flip-chip UBM, and asymmetric top/bottom metallization—this device enables seamless integration into specialized packaging flows including flip-chip, embedded die, and chip-on-board assemblies. Built on a fully configurable platform, this device is tailored to your capacitance (5 pF–1,000 pF), voltage (6.3 V–100 V), chip geometry, and metallization requirements with rapid prototyping turnaround.

Minimal Dissipation Factor (tan δ) Under RF Power

In high-power RF circuits—transmitter output matching networks, antenna tuning units, and power amplifier drain bias decoupling—the capacitor's dissipation factor directly converts a fraction of the RF power into heat. At +40 dBm (10 W) continuous wave, even a modest tan δ of 0.005 (0.5%) generates 50 mW of localized heating within the capacitor die. The HACC500S50V500 eliminates these power-handling compromises through a fundamentally low-loss materials system:

1. SiO&sub2; Dielectric — Intrinsically Low tan δ: The 300 nm thermally-grown silicon dioxide dielectric has a dissipation factor below 0.001 (0.1%) at 1 GHz—an order of magnitude lower than the 0.5–2% tan δ typical of Class II X7R ceramics at the same frequency. SiO&sub2;'s wide bandgap (8.9 eV) and purely covalent bonding leave no polarizable ionic species or ferroelectric domains to dissipate RF energy through dielectric relaxation. The result is a dielectric loss tangent that remains below 0.001 from 100 MHz to 10 GHz, tested and verified on every production lot.

2. Verified Low-Loss Under Full RF Power Excitation: tan δ in real capacitors can increase with RF drive level due to nonlinear dielectric response, electrode heating, and substrate conductivity modulation. The HACC500S50V500 is characterized under actual RF power conditions: at 1 GHz with +40 dBm (10 W) CW excitation, dissipation factor remains below 0.001. At 10 GHz with 1 W CW, tan δ stays below 0.003. This power-stable loss characteristic is achieved through high-resistivity float-zone silicon substrate (>1,000 Ω·cm) minimizing substrate-induced eddy current losses, combined with thick 2.5 μm gold top electrode for minimal I²R ohmic losses at microwave frequencies.

3. Thermal Management for Sustained High-Power Operation: The 0.15 mm ultra-thin profile and high-conductivity backside TiW-Pt-Au metallization provide a thermal resistance (θ_JC) below 15°C/W when attached with AuSn eutectic solder—meaning a 10 mW dissipation produces less than 0.15°C junction temperature rise. The thermal time constant is below 1 μs, ensuring that even under pulsed RF operation (radar, TD-LTE) with high peak-to-average power ratios, the capacitor temperature follows the average power, not the peak envelope power.

Custom Metal Layout for Specialized Packaging

Standard chip capacitors impose a one-size-fits-all metallization. The HACC500S50V500 breaks free of these constraints through a fully customizable metal layout platform:

Custom Top Electrode Configurations:

• Selective Gold Thickness: Standard 2.5 μm Au with options for thickened regions up to 5.0 μm at bond pad locations for heavy-wire or ribbon bonding. The photolithographic lift-off process enables arbitrary spatial variation in gold thickness across a single die
• Patterned Multi-Pad Layouts: Top metallization can be patterned into multiple electrically-isolated or common-connected pads—enabling Kelvin (4-wire) connections, separate RF and DC bias pads, or independent capacitor channels within a single die. Pad sizes, shapes, and positions are defined by your mask design
• Flip-Chip UBM Integration: Top electrode can be finished with Under-Bump Metallization (TiW/Cu/Au or electroless Ni/Au) compatible with solder bump deposition (SnAg, SnAgCu, AuSn). Solder bump arrays (80–150 μm diameter, 150–250 μm pitch) enable direct chip-to-carrier attachment without wire bonds
• Asymmetric Top/Bottom Metallization: Independently selectable top and bottom metallization stacks—one face for flip-chip UBM, the other for standard TiW-Pt-Au conductive epoxy die attach—enabling hybrid assemblies

Custom Backside Metallization Options:

• AuSn Pre-Deposition: 3–5 μm of 80Au/20Sn eutectic solder pre-deposited on the backside, enabling flux-free eutectic die attach without separate solder preforms
• Patterned Backside for Multi-Point Grounding: Backside metallization segmented into multiple isolated or common-connected ground pads, enabling separate RF and DC ground returns within the same die
• Aluminum Backside for Wire-Bond Ground: For assemblies where backside die attach is not the ground connection method, enabling wedge bonding of ground wires directly to the capacitor's back face

Custom Die Geometry: Non-standard footprints up to 5.0 × 5.0 mm, rectangular aspect ratios up to 4:1 (e.g., 0.25 × 1.00 mm), and irregular geometries (L-shape, T-shape, annular, polygonal) fabricated through customer-defined dicing street maps, enabling capacitor integration into existing hybrid circuit layouts without layout redesign.

Key Electrical Specifications

• Capacitance: 50 pF ±10% (±5% optional), measured at 1 MHz, 1.0 Vrms, 25°C
• Rated DC Voltage: 50 V continuous
• Dielectric Withstanding Voltage: >125 V (250% rated), 5 sec dwell, 100% production tested
• Dissipation Factor (tan δ) @ 1 GHz: <0.001 (<0.1%), maintained to +40 dBm RF power
• tan δ @ 10 GHz: <0.003, verified under 1 W CW excitation
• RF Power Handling: Up to +40 dBm (10 W) CW, verified low-loss operation
• Dielectric Type: Thermal SiO&sub2;, 300 nm (low-loss paraelectric)
• Q Factor @ 1 MHz / @ 1 GHz: >2,000 / >300
• ESR @ 1 GHz: <0.08 Ω
• Intrinsic Chip ESL: <0.05 nH
• Thermal Resistance (θ_JC): <15°C/W (AuSn eutectic attach)
• Temperature Coefficient of Capacitance (TCC): +35 ppm/°C (-55°C to +125°C)
• Operating Temperature Range: -55°C to +125°C
• Insulation Resistance: ≥10⁴ MΩ @ Rated Voltage DC, 25°C
• Dielectric Absorption: <0.1% @ 1 kHz
• Moisture Sensitivity: MSL 1 (Unlimited floor life per J-STD-020)
• Storage Temperature: -65°C to +150°C
• ESD Rating: Class 0 (HBM) per JESD22-A114

Physical & Construction Specifications

• Chip Dimensions: 0.50 × 0.50 × 0.15 mm (±25 μm standard); custom geometries up to 5.0 × 5.0 mm
• Design Architecture: Double-Sided Bordered (Margin)
• Substrate: Float-Zone Si, >1,000 Ω·cm
• Top Metallization: TiW-Au, ≥2.5 μm Au; custom thickness up to 5.0 μm; patterned layouts available
• Backside Metallization: TiW-Pt-Au, ≥1.0 μm Au with Pt diffusion barrier; custom stack available
• Wire Bond Pull Strength: >6 gf for 25 μm Au wire (MIL-STD-883 Method 2011.7)
• Chip-Level SRF: >2 GHz (no bond wire, de-embedded)
• System SRF (0.5 mm bond wire): >800 MHz (single 25 μm Au wire)
• Mounting Type: Wire Bondable / Flip-Chip / Conductive Epoxy or AuSn Eutectic Die Attach
• Compliance: RoHS Compliant (EU 2015/863), Halogen-Free per IEC 61249-2-21, REACH SVHC Free

Typical Applications

• High-power RF transmitter output matching networks (up to 10 W CW)
• GaN power amplifier drain bias decoupling
• Antenna tuning unit capacitors for cellular base stations
• Industrial RF plasma generator matching (13.56 / 27.12 MHz ISM bands)
• Flip-chip integrated passive device (IPD) modules
• Multi-chip modules with custom interconnect requirements
• Embedded die packaging with non-standard metallization needs

Customization Platform — Design to Your Specification

The HACC500S50V500 is built on a fully configurable MOS capacitor platform. Submit your metal layout requirements in GDSII or DXF format for feasibility assessment within 2 business days:

• Capacitance: 5 pF to 1,000 pF; ±5% or tighter tolerance available
• Rated Voltage: 6.3 V DC to 100 V DC
• Top Metallization: Selective Au thickness up to 5.0 μm; patterned multi-pad; flip-chip UBM (TiW/Cu/Au or electroless Ni/Au); Al-metallized options
• Backside Metallization: Au-only; AuSn/AuGe/AuSi pre-deposition; patterned backside for multi-point grounding; Al backside for wedge bonding
• Flip-Chip Bump Configuration: Solder bumps 80–150 μm diameter, 150–250 μm pitch; SnAg, SnAgCu, or AuSn
• Chip Dimensions: 0.25 × 0.25 mm to 5.0 × 5.0 mm; rectangular up to 4:1 aspect ratio; irregular geometries (L-shape, annular, polygonal)
• Dielectric Options: Custom SiO&sub2; thickness 50–5,000 Å; SiN or Al&sub2;O&sub3; high-K for higher density requirements
• Prototype Lead Time: 3–4 weeks standard; expedited 1–2 weeks for standard capacitance values