Silicon Capacitors

Image	Part Number	Description / PDF	Quantity	Rfq
	RFCS04023000DBTTS Vishay	CAP SILICON 0.3PF 50V 0402	0
	RFCS04021000CBTWS Vishay	CAP SILICON 1PF 50V 0402	0
	RFCS04027000DBTTS Vishay	CAP SILICON 0.7PF 50V 0402	0
	RFCS04021800BJTWS Vishay	CAP SILICON 18PF 16V 0402	0
	RFCS04024700CJCT1 Vishay	CAP SILICON 4.7PF 25V 0402	0
	RFCS04024700CBCT1 Vishay	CAP SILICON 4.7PF 25V 0402	0
	RFCS04023000CJCT1 Vishay	CAP SILICON 3PF 0402	0
	RFCS04028200CJTT1 Vishay	CAP SILICON 8.2PF 5% 25V 0402	0
	RFCS04026000DBTTS Vishay	CAP SILICON 0.6PF 50V 0402	0
	RFCS04021200BJTT1 Vishay	CAP SILICON 12PF 5% 16V 0402	0

Silicon Capacitors

1. Overview

Silicon capacitors are a class of capacitors fabricated using silicon-based materials and semiconductor processes. They offer high capacitance density, excellent temperature stability, and low equivalent series resistance (ESR). These capacitors are critical in modern electronics for applications requiring miniaturization, high reliability, and performance in extreme environments. Their integration with silicon wafers enables compatibility with advanced IC manufacturing processes, making them essential in RF circuits, power management, and high-frequency systems.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Metal-Insulator-Metal (MIM) Silicon Capacitors	High linearity, low parasitic inductance, stable over temperature	RF ICs, analog circuits, decoupling in SoCs
Polysilicon Capacitors	High-temperature endurance, moderate capacitance density	Automotive sensors, industrial control systems
Trench Silicon Capacitors	High capacitance per unit area, low leakage current	Power management ICs, DC-DC converters
Superjunction Silicon Capacitors	Ultra-low ESR, high ripple current tolerance	High-frequency power supplies, 5G base stations

3. Structure and Composition

A typical silicon capacitor consists of: - Silicon Substrate: Monocrystalline or polycrystalline silicon wafer serving as a base. - Dielectric Layer: Silicon dioxide (SiO ) or silicon nitride (Si N ) for insulation. - Electrodes: Aluminum, copper, or doped polysilicon layers deposited via sputtering or electroplating. - Passivation Layer: Silicon carbide (SiC) or epoxy coating to prevent environmental damage. The structure is optimized for minimal parasitic effects and integration with CMOS processes.

4. Key Technical Specifications

Parameter	Description	Importance
Capacitance Range	0.1 pF to 100 F	Determines charge storage capability
Voltage Rating	2.5V to 100V	Defines safe operating limits
Tolerance	1% to 20%	Affects circuit precision
Temperature Coefficient	50 ppm/ C to 500 ppm/ C	Stability over temperature variations
ESR (Equivalent Series Resistance)	1 m to 50 m	Impacts high-frequency performance
Operating Temperature	-55 C to +150 C	Defines environmental robustness

5. Application Fields

Consumer Electronics: Smartphones (RF filters), laptops (power decoupling).
Telecommunications: 5G base stations (high-frequency bypass capacitors).
Automotive: Engine control units (ECUs), LiDAR systems.
Industrial: Motor drives (snubber circuits), solar inverters.
Aerospace: Satellite power systems, avionics.

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Murata Manufacturing	SiC-HP Series	High-temperature stability for automotive applications
TDK Corporation	CGA Silicon MLCC	MIM structure for 5G RF front-ends
Vishay Intertechnology	VJ HIFREQ Silicon	Ultra-low ESR for high-frequency power circuits
Infineon Technologies	OptiMOS Trench Capacitor	Integrated with MOSFETs for energy efficiency

7. Selection Guidelines

Consider the following factors: - Capacitance and Voltage Requirements: Match ratings to circuit specifications. - Frequency Response: Prioritize low ESR for high-frequency applications. - Environmental Conditions: Select temperature ratings for automotive/aerospace use. - Package Size: Use chip-scale packages for space-constrained designs. - Cost vs. Performance: Balance precision (tight tolerance) with budget constraints.

8. Industry Trends

Key trends shaping silicon capacitors include: - **Advanced Packaging:** 3D stacking and through-silicon vias (TSVs) for higher integration. - **Material Innovations:** Adoption of hafnium oxide (HfO ) for higher dielectric constants. - **Miniaturization:** Sub-micron trench structures for mobile devices. - **High-Temperature Performance:** Growth in EV and renewable energy systems requiring thermal resilience. - **Green Manufacturing:** Reduction of hazardous materials in fabrication processes.