What is RF Schottky Diode : Benefits & Top Manufacturers

An RF Schottky diode is a high speed semiconductor device characterized by low forward voltage drop, fast switching speed, and excellent high frequency performance. It is widely used in RF detectors, mixers, rectifiers, frequency multipliers, power sensors, and microwave communication circuits. Popular manufacturers of RF Schottky diodes include ON Semiconductor, NXP Semiconductor, ROHM Semiconductor, MACOM, and M-Pulse Microwave.

Figure 1 depicts a Schottky diode structure and its equivalent circuit. As shown, it is formed using metal-semiconductor junctions at both ends. Metals such as chromium, tungsten, aluminum, platinum, and gold are used in its construction. It utilizes N-type silicon as the semiconductor material. The Schottky diode is constructed on a thin silicon (n+ type) substrate by epitaxially growing an n-type active layer of about 2 microns thickness. The metal-semiconductor junction is formed by depositing metal over SiO2.

The circuit symbol of a Schottky diode is shown in Figure 2.

Figure 3 illustrates the characteristic of a Schottky diode. As shown, the V-I curve is steeper compared to a traditional p-n junction diode. From the curve, we can conclude that Schottky diodes exhibit a square law characteristic.

RF Schottky diode Selection Guide

The following parameters are considered when selecting a Schottky diode for your needs:

• Peak Reverse Voltage
• Forward Voltage
• Current Surge Peak
• Reverse Leakage Current
• Capacitance
• Recovery Time
• Working Temperature
• Package Type

Advantages of RF Schottky Diodes

Here are some of the benefits of using Schottky diodes:

1. Low Forward Voltage Drop: Reduces power loss and improves efficiency in RF and microwave circuits.
2. High Switching Speed: Enables fast signal processing, making it ideal for high-frequency applications like mixers and detectors.
3. Low Capacitance: Minimizes signal distortion and enhances performance in RF rectification and switching applications.
4. Efficient Signal Detection: Commonly used in RF power detectors and envelope detectors due to its ability to detect weak signals effectively.
5. Supports Wide Frequency Range Operation

RF Schottky Diode Manufacturers

The following table lists RF Schottky diode manufacturers along with their part numbers and technical features.

RF Schottky Diode Manufacturers	Description
ON Semiconductor	• Part numbers: NSR15SDW1T1, NSR15SDW1T2 • They are designed for analog/digital applications viz. mixing, DC-based signal detection. • Major features are low capacitance, low VF, low VFΔ etc. • Visit following website for more Schottky diodes. • Website: onsemi.com
NXP Semiconductor	• Part numbers: PMEG6045ETP, 1PS70SB84 • Read datasheets on the NXP company website for their technical specifications, package types, and dimensions. • Website: nxp.com
ROHM Semiconductor	• Part Number: RB876WTL • Major features are ultra-small mold type, low capacitance, and highly efficient radio detection • Read data sheet at website: rohm.com for more technical specifications.
MACOM USA	• Model: MA4E1338 series • Applications: Mixer, Detector, and Limiter circuits • Features: 8 V Schottky Diode, RoHS Compliant, operating frequency from DC to 6 GHz • Configurations available are single diode, series pair, unconnected pair • Visit Website macom.com for more part numbers.
M-Pulse Microwave	• Part number: MP2052 • Features: Supports frequencies up to 18 MHz, 1V peak reverse voltage, 3mA forward current, and so on. • Visit website mpulsemw.com for more part numbers.

Summary

RF Schottky diodes provide fast switching and low-loss operation for RF and microwave circuits. Leading manufacturers develop Schottky diodes for detectors, mixers, power sensors, and communication applications.