Utilizing our 35 years of experience in optoelectronics, Marktech’s customization process focuses on customer needs and applications. Instead of using standardized–but perhaps non-optimized–parts, Marktech allows advantageous custom product variations to enhance your product design.

Custom packaging and electrical sorting of product offer further differentiation. Marktech provides the designer with insights concerning custom variations–variations that optimize electrical, optical, and thermal characteristics–without the need for large volume commitments. In addition to our headquarters in New York where we have both our design engineering staff and complete testing department for all optical and electrical parameters we also have two manufacturing facilities in California and Japan, Marktech is a vertically-integrated company, allowing us to produce detector components quickly, thus decreasing your time to market. We can even produce your entire package in the United States.

To solve your needs, Marktech engineers will discuss with you:

• Application needs specific to your project
• Optimization of component and assembly packaging, technology, thermal and electrical parameters
• Manufacturing of dedicated end-products in support of your specifications and needs

In this article we focus on optoelectronic Detector Materials, to allow options to customize detector components for optimal mating with compatible emitters.

Overview

Photodetectors are sensors, detecting light and converting the photons into measurable currents, and are therefore useful for applications ranging from water faucets to nuclear transient events. With varied technologies and packaging, specific measurements can be made that are ideal for your applications.

Marktech devices are solely solid state devices (there are no photomultiplier tubes in our product line, although our products may supply similar functionality). Response rates can be as fast as 300 picoseconds. Light levels that can be measured range from tens of photons to massive levels. Wavelengths can range from 250nm to greater than 3000nm.

Each photodetector uses a p-n junction as part of either a photodiode or phototransistor construction, effectively working as an inverse function from the typical operation of a light emitting diode. Depending on the technology used, the detectors provide current response to specific ranges of light wavelength.

Detector Materials and Characteristics: The materials used may be Silicon or InGaAs. The P and N epitaxial layers of the wafer materials can be optimized for specific customer specifications and desired characteristics, including Minimum Reflection, Low Dark Current, Minimum Series Resistance, Low Capacitance, Fast Response, Low Cross Talk, and more. The detectors can be packaged in a variety of packages from metal can and standard 3mm and 5mm plastic packages, to surface-mount…or virtually any custom package assembly. Detector applications range from simple door opening to the latest cancer PET scan system.

Detector Wavelengths Available products have wavelengths varying from 250nm (UV) through the visible region (440 to 700nm), through SWIR short wavelength infrared (up to 2600nm). This link to an online Product Selector Guide helps in the selection of the emitter wavelengths, while also indicating compatible detectors. Tight binning by Marktech can provide uniform color characteristics to optimize the application and mating detectors’ sensitivities, providing process controlled uniform product solutions.

Marktech Photodetector variations

Silicon Photodetectors (400nm to 1100nm): photovoltaic, photoconductive photodiodes and phototransistors

• Silicon Avalanche Photodiodes (400nm to 1100nm, with 800nm, 905nm optimization)
• UV Detectors (250nm-450nm)
• InGaAs PIN Photodetectors (600nm – 1750nm) for SWIR (Short Wavelength IR) detectors

Products are also available in Epitaxial Wafer form, and can be packaged as Photoreflectors, arrays and hybrid parts. For part listing and additional information, see: http://marktechopto.com/marktech-detectors.cfm

Silicon Photodetectors (400nm to 1100nm): Marktech’s silicon phototransistors can be utilized in applications requiring very high sensitivity, uniform response, and increased reliability for applications that require very high sensitivity, uniform response and increased reliability such as card readers and optical sensors.

The photovoltaic silicon photodetectors have a spectral sensitivity from near ultraviolet, through the visible range, to short wavelength infrared (400nm to 1100nm). These are used in applications such as medical, analytical, communications, spectroscopy equipment, and sensing requiring broadband sensitivity with enhancements in the blue/green region. These devices can exhibit moderate-speed response, high sensitivity, and low noise. Devices are available as either phototransistors or photodiodes.

The Photoconductive silicon photodetectors are suitable for high speed and high sensitivity applications. The spectral range extends from 350 to 1100 nm, making these photodiodes ideal for visible and near IR applications, including such AC applications as detection of pulsed LASER sources, LEDs.

Marktech’s broad line of silicon photodetectors are provided in a variety of package types ranging including through-hole plastic, ceramic, metal-can, surface mount, and full custom. These devices are available with standard silicon die having a spectral sensitivity of approximately 400nm – 1100nm, or with special UV enhanced silicon chips with sensitivity in the lower UV-A range. Custom active areas and multi-element chips can also be manufactured to suit your application. Many of our wafers/chips are manufactured in the USA and optimized to insure uniform and consistent performance with high reliability. These devices are well suited for visible and near IR applications requiring high speed and high sensitivity as well as low noise such as optical switches and optical communications.

Marktech silicon detectors can be obtained with integrated filters for reduced visible light interference or optimized for your required spectral range. In addition to our various package styles available off-the-shelf, Marktech can integrate multiple detectors and/or emitter detector combinations in a single package type.

Silicon photodetector variations:

• Silicon Phototransistors
• Silicon Photodiodes in SMT, through-hole DIL, and metal can packaging
• Photodiode Arrays
• Dual/Quadrant Photodiodes
• Multichip photodiodes for expanded wavelength or sensitivity
• Silicon Photovoltaic PIN photodiodes
• Silicon photoconductive PIN photodiodes
• Silicon PIN Photodiodes with enhanced blue sensitivity
• Silicon photodiode arrays
• Differential photodiodes

Customized Optimizations

• UV Blue Green NIR (Near IR) 1064
• InGaAs 1700nm-2600nm
• Minimum reflection
• Low dark current
• Minimum series resistance
• Low capacitance
• Low carrier lift time
• Fast response
• Low cross talk

Customized Packaging

• Tested wafers
• Chips
• Hermetic packaged devices
• Hybrids (Detector/Amplifier in one package)
• Detector/filter combinations (Bandpass or color glass)
• Hybrid/Modules (Ceramic or COB (chip on board))

Typical industries served Medical, Optical Communications, Industrial, Scientific and Analytical

Common applications: Remote Controls, Optical Encoders, Position Sensors, Fiber optics, Bar code readers and chemical analysis

Silicon Avalanche Photodiodes (400nm to 100nm, optimized for 800nm, 905nm):

Avalanche photodiodes are ideal for high-speed and low-light level detection in the near-infrared range. These detectors have become the semiconductor equivalent of photomultipliers in many applications including data communication, LIDAR, instrumentation and photon counting. In addition cost effective customization of these APDs is offered to meet exacting design specifications. Operation voltage selection and breakdown voltage (Vbr) binning, wavelength specific band-pass filtering and hybridization options are among many of the application-specific solutions available at Marktech.

Marktech APD’s have an internal gain mechanism, fast time response, low dark current and high sensitivity in the near infrared region. These APD’s are recommended for applications that require high bandwidth, or where internal gain is needed to overcome high pre-amp noise. In addition, Marktech APD’s provide higher sensitivity than a standard photodiode and are ideal for extreme low-level light detection and short pulse detection. APDs are essentially photodetectors that provide an amplification gain stage through avalanche multiplication. They are similar to photomultipliers, but are solid state semiconductor devices.

Silicon Avalanche photodiodes (Si APD’s) are the preferred optical detectors for applications where the wavelength lies between 400nm and 1100nm (with 800 and 905nm optimized sensitivities), and exhibit high speed and low noise for visible to near IR applications. Standard versions are available in three active area diameter sizes: 200, 500 & 800um and are offered in hermetic TO Cans, and can also be supplied in cost effective LCC packages.
TUV Detectors (250nm – 450nm)

UV LEDs/emitters are becoming more prevalent in the industry, replacing old technology such as mercury lamps. As a result, the need for UV detection is also increasing. Marktech offers new UV enhanced Silicon based UV detectors in a variety of metal-can thru-hole type packages ranging from TO-18 – TO-39 with special UV glass to insure optimum lifetime and the least amount of material degradation. In addition, we will be introducing a new hermetically sealed surface mount package with a glass cover for those applications requiring low profile and high reliability. These new “seam welded” devices will be available on a production basis the first quarter of 2021. Marktech offers both standard and custom package solutions in bare chip, component or assembly form to meet your application requirements.
Marktech UV detectors offer superior stability over time and high device sensitivity with low dark current.

Typical Industries Served

Medical, Industrial, Scientific and Analytical, Environmental/Ecological and Commercial.

Common Applications Biomedical/Chemical Analysis, UV emitter output monitoring, UV Sensors, Spectrometers and Wearables.

InGaAs PIN Photodetectors (600nm – 2600nm)

This high-sensitivity and high-reliability product series is ideally suited for applications in the SWIR (short wavelength infra-red) wavelength range. communication devices.

Photodiode chip active area sizes from 0.1mm to 3.0mm are available to provide the optimum balance between low dark current, high speed and light sensitivity. This allows for increased flexibility and options in a variety of applications ranging from fiber optics and high speed optical communications to medical and chemical analysis.

Integrated TE (Thermal Electric) Cooling is not utilized on any of our PIN Photodiodes, thereby reducing costs and improving overall efficiency.

In addition to PIN Photodiodes, Marktech offers foundry services for epitaxial growth of SWIR wafers in the 1.0 um to 2.6um range, using InP material as the base substrate. Marktech is currently producing these high reliability wafers in 2″, 3″ and 4″ diameters. Among the applications for these wafers are photodetectors, linear arrays and image sensors. Photodetectors processed using our epitaxial wafers provide significant advantages, including lower dark current, better shunt resistance and overall improved performance at lower operating temperatures.

Marktech manufactured InP PIN Photodiodes using InGaAs/InP technology have a spectral sensitivity in the 800nm to 1750nm range for applications requiring low dark current, high speed and sensitivity such as fiber optics and optical communications. Marktech’s detector die can be placed in a variety of packages from metal can TO-5, TO-18 and TO-46 to surface mount and standard 3mm and 5mm plastic packages. We can also incorporate the detector die in custom designed assemblies.

SWIR (Short Wavelength IR) detectors (1050nm to 1720nm)

Marktech Optoelectronics is one of only a handful of manufacturers that supply emitters in the extended wavelength or SWIR range. Marktech’s standard product offering includes both through-hole and surface mount packages with wavelengths from 1050nm to 1720nm and operating currents ranging from 20mA to 350mA for high-power applications. Higher wavelength ranges up to 3000nm are available in specific package types (see MWIR below).

The SWIR wavelength range requires specialized optical detectors, since standard silicon detectors have a maximum sensitivity limit of up to only approximately 1100nm. Marktech produces a line of InGaAs detectors that are optimized for sensing light in this SWIR wavelength range. These detectors can be obtained as an individual, discrete component, or they can be combined with a silicon sensor to cover the complete spectrum of light from the visible to the SWIR range. Marktech also offers the option to custom-produce multi-element devices with emitter and detector chips in the same package.

The Marktech extended wavelength standard SWIR package offerings include:

• TO-46 flat
• TO-46 lens
• TOPLED PLCC4
• SMD 1206
• SMD 1206 Lens
• SMD high-power black

MWIR (mid-wavelength IR) Detectors (>3000nm)

Extended wavelength detectors: If you require above 3000nm, which is more in the MWIR [mid-wavelength infrared] range, Marktech has a team of experienced engineers to work with you to develop a custom wafer or die that meets your specific application needs.
Marktech’s optoelectronic manufacturing and assembly capabilities include:

• SMD, thru-hole, and chip on board assembly
• High-density pick and place
• Prototyping
• Small to high-volume production runs
• PCB design and fabrication
• Single or multi-layer
• Flexible or rigid
• Aluminum, FR4, ceramic, and polyimide
• Schematic capture
• PCB design
• CAD/CAM
• Consigned or purchased materials
• In-circuit testing
• Reliability testing
• Potting
• Conformal coating
• IPC standard assembly
• Use of your Part Numbering System
• Shipped to your packaging requirements

Additional outsourced capabilities include

• Plastic injection molding
• Metal work fabrication
• Optical analysis
• Thermal analysis

Applications
Applications:

• Astronomy:
  • Space based telescopes with far IR wavelengths
• Automotive:
  • Driver vision in low light
  • collision detectors
  • Twilight detection
• Banking:
  • Counterfeit detection in currency
• Communication:
  • Fiber optic communication typically operates in the infrared (IR) wavelength, with very high rise time (response rate) to allow high data rates of up to 100 Gigabits/second. Silicon photodiodes are used for short wavelength links (650 for POF and 850 for glass MM fiber). Long wavelength systems usually use InGaAs (indium gallium arsenide) detectors as they have lower noise than germanium which allows for more sensitive receivers. Very high speed systems sometimes use avalanche photodiodes (APDs) that are biased at high voltage to create gain in the photodiode.
• Chemical/biological
  • high speed detection
• Consumer:
  • Household electronics: radios, DVD players, TV, Computer sensors
  • Cameras
• Environmental:
  • Detection via spectroscopy for pollutants and particulates
  • Global temperature monitoring via space-based sensors
  • Thermal imaging for home and business heat loss/efficiency
  • Recycling: Material identification from fluorescence of plastics/ glass
• Industrial:
  • Robotic imaging, sensing
  • Video camera imaging
  • process control through temperature monitoring
  • Arc light detection. Ultraviolet wavelength detectors are offered in applications where mercury lamps and UV LED’s are used.
  • Bar coding
• Medical:
  • Pulse oximeters
  • CAT, PET scans
• Military:
  • Night vision applications
  • Intake, Exhaust temperatures for aerospace
• Municipal
  • Monitoring of water purification for municipal water supply, pools
• Safety/ Security
  • Smoke/flame detection
  • TSA security

SWIR FOR NIGHT VISION APPLICATIONS

Arrays of SWIR detectors have been utilized in SWIR night vision systems which rely on the intense night glow that can illuminate the scenery even when there is complete darkness in the visible spectrum.

HOMELAND SECURITY

APPLICATIONS IN MEDICAL & BIOPHOTONICS

APPLICATIONS IN BIOPHOTONICS/BIOMEDICAL

SWIR detectors can help realize the non-invasive imaging methods, for example, optical coherence tomography (OCT) systems utilizing SWIR exploit the low scattering properties of >1μm light to see the previously unreachable, thick parts of the cornea.

SWIR INDUSTRIAL APPLICATIONS

Inspection for High Temperature Manufacturing Processes
Web inspection of continuous process such as high temperature manufacturing processes and quality controls.

RECYCLED PLASTICS & RESORTING

SWIR can be used in recycled plastics industry, due to C-H, O-H and N-H found in plastics, and used wavelength around 1.0-2.2μm.

APPLICATIONS IN AGRICULTURE

SWIR detectors, such as 1240nm, 1640nm and 2130nm, combined with visible detectors can be applied in some remote sensors for soil moisture and agricultural drought monitoring.

SWIR imaging can provide more information about Rock and Soil features better than visible images, due to the reflection characteristics of rock and soil in the 1.8 – 2.5um region.

LIDAR

LIDAR (Light Detection and Ranging) is a surveying method that measures distance to a target by illuminating that target with a laser light. LIDAR uses laser light pulses, while radar uses radio waves. Avalanche Photodiodes enable the LIDAR application as a remote sensing technology that optically measures properties of scattered light to find range and/or other information of a distant target.