Q&A with Marktech Optoelectronics and its ATLAS packaged InGaAs photodiodes

Marktech Optoelectronics, based in Latham, New York,recently won Best of Sensors in the Aerospace category at Sensors Converge 2023, featuring its new ATLAS packaged InGaAs photodiodes.  Gary Kardys, business development manager, offered Fierce Electronics insights on the technology, its place in the market and possible uses—from medical devices to spacecraft and many other mission critical applications.

Fierce Electronics: What are the key features and specifications of the new ATLAS packaged InGaAs photodiodes?

Marktech Optoelectronics: The ATLAS packaged InGaAs (Indium gallium arsenide) photodiodes are highly sensitive photodetectors designed for near-infrared (NIR) and short-wave infrared (SWIR) applications. They feature a compact and low profile package. The ATLAS photodiodes are available in two wide spectral response ranges of 600nm to 1700nm (1.7µm cutoff) and 800nm to  --- 2600nm (2.6µm cutoff). In some applications, the broad spectral detection range eliminates the need for an additional silicon photodiode. However, we also provide products with multiple InGaAs and silicon photodiodes in the same package where UV sensitivity is required.

ATLAS InGaAs photodiodes provide exceptional detection performance with low noise, low dark current, high responsivity, and fast response times. Our InGaAs photodiodes have active areas from 0.08mm to 3.0mm. The 0.08mm active area InGaAs photodiode provides remarkably high speed or low response time, while our 3.0mm InGaAs photodiode has high gain. A 5.0mm active area InGaAs photodiode product is being developed and will be released in 2023 to provide an even higher gain. In addition, versions are available with built-in thermoelectric coolers (TECs) and transimpedance amplifiers (TIAs) to reduce noise further and enhance the signal-to-noise ratio.

The ATLAS packaging containing our InGaAs photodiodes provides exceptional protection against the ingress of water vapor and gas contaminants, which degrades semiconductor materials, reducing performance. ATLAS packaging provides the hermetic seal integrity of TO-can packaging in surface mount device (SMD) format. SMD packaging is desirable for high-volume applications, but conventional plastic SMD packages suffer from outgassing and are non-hermetic – so they do not protect the semiconductor detector chip. On the other hand, the ATLAS package is constructed with only ceramic, glass and metallic components so that no internal outgassing can occur and no external vapor contaminants can enter the package. In addition to improved assembly characteristics, the ATLAS package has a smaller footprint and profile, which is essential in a world where sensor, instrument, and wearable designs continue to shrink in size.

Fierce Electronics: What differentiates ATLAS photodiodes from similar products in the market, and what advantages do they offer to potential users?

Marktech Optoelectronics: The new product encompasses innovations at two levels:

1. Compound Semiconductor – The InGaAs photodiode represents the culmination of many years of research and engineering to develop an infrared detector with the ultimate responsivity. To the best of our knowledge, our 2.6 micron InGaAs detectors have the highest sensitivity on the market.

2. Photonic Packaging – Our unique optotelectronic package provides the hermeticity of a transistor outline or TO-can package in the compact, low profile form factor of a surface mount device (SMD) package. Printed circuit board (PCB) assembly using surface mount technology (SMT) is generally considered superior to leaded or through-hole assembly – especially in high volume applications. With SMT assembly, components can be mounted on both sides of a PCB, so more components/PCB means better size, weight, and power (SWaP) characteristics. TO-can or through-hole devices with leads require PCBs with holes for soldering, which limits the PCB part density.

In a nutshell: Revolutionary Performance and Reliability for Infrared Sensing Combined with Improved Manufacturability:

1.  Unexcelled Infrared Detection Performance - ATLAS photodiodes exhibit high responsivity or sensitivity, enabling high signal-to-noise ratios and enhancing the overall sensitivity and reliability of the device. Some customers have told us we outperform all competitors they have tested in their designs.

2.  Longevity and Reliability – In space applications, reliability is paramount –you typically do not get second chances or have the ability to replace or repair a device. The hermetic ceramic-metallic, glass ATLAS packaging assure long, accurate, and consistent performance for years. The airtight or sealed nature of the product prevents water and moisture from entering the package. Conventional SMD packages do not have this feature. 

3.  Small footprint and low profile or desirable Size, Weight, and Power (SWaP) characteristics suitable for most design projects.

4.  Compared to TO-cans, the ATLAS package provide improved manufacturability. ATLAS components can be reflow soldered using surface mount technology, which is desirable for high-volume production compared to leaded or through-hole technology.

Fierce Electronics: What applications and industries are ATLAS photodiodes particularly suited for?

Marktech Optoelectronics: They are well-suited for medical diagnostics, optical communications, spectroscopy, moisture and gas sensing, infrared or optical pyrometry, aerospace, industrial process control, environmental monitoring, laser monitoring, and scientific research. Their wide spectral response range makes them ideal for detecting and measuring near and short-wave infrared light in these fields. The compact size and low profile hermetic package provides a useful feature for wearable medical devices and spacecraft sensors.

We can backfill the package with nitrogen or other gases to provide spacecraf -worthy InGaAs photodiode detectors. We can test and qualify these space-rated components to Mil-Standards when required. We can test to high vacuum levels 10-9.

Fierce Electronics: How does Marktech Optoelectronics ensure the reliability and quality of the ATLAS photodiodes during the manufacturing process?

Marktech Optoelectronics: Marktech is an integrated infrared detector producer, so we can control the production and quality of the InGaAs photodiodes from MOCVD depositions processes during the development of the InGaAs structures on the Indium Phosphide (InP) wafers, to fabrication of the photodiode chips and finally to the packaging and assembly into a finished IR photodetector.In addition, at Marktech Optoelectronics, we prioritize the reliability and quality of our products. The ATLAS photodiodes undergo rigorous manufacturing processes and testing to ensure consistent performance. We adhere to stringent quality control standards and utilize advanced manufacturing techniques to minimize variations in the device characteristics. Additionally, our photodiodes undergo thorough reliability testing to meet industry standards and provide reliable operation over extended periods.

Fierce Electronics: Are there any plans for future enhancements or developments for the ATLAS packaging and your InGaAs photodiode product line?

Marktech Optoelectronics: As a company committed to innovation, Marktech Optoelectronics continuously strives to enhance its product offerings. We have an ongoing roadmap for the ATLAS photodiode product line, which includes plans for further improvements and expansions. Future enhancements may involve increased responsivity, reduced noise levels, expanded wavelength range options, and optimized packaging designs to meet evolving customer requirements. Stay tuned for exciting developments in the ATLAS photodiode series.In addition, we are introducing ATLAS packaged UV, visible, and NIR LED emitters because many optical sensing and spectroscopy applications require two components: a light source or emitter and a photodetector. Marktech even has products with InGaAs detectors combined with visible, NIR and SWIR LEDs in the same package, which can be ideal for reflective and functional near-infrared spectroscopy (fNIRs) applications. We are also developing larger versions of the ATLAS package to house InGaAs and silicon photodiodes with larger active areas. For instance, a 5mm active area InGaAs detector is coming soon.

While the ATLAS package is outstanding from a reliability and assembly manufacturing viewpoint, Marktech also has a broad array of packaging types for LEDs and photodiodes such as TO-can, PLCC, ceramic SAW, chip-on-board (COB), and we routinely design custom packages for our customers.

Fierce Electronics: Congratulations on winning Best of Sensors in Aerospace at the 2023 Sensors Converge Conference and Exposition. What are some of Marktech’s core competencies that facilitated the development of this infrared detection innovation?

Marktech Optoelectronics: We are honored by the Best of Sensors award from Fierce Electronics –especially considering the many leading sensors manufacturers in the competition at Sensors Converge, the leading event for design engineers.Unfortunately, we cannot reveal the customer names and specific details of the space or aerospace projects due to non-disclosure agreements (NDAs). We have signed over 300 NDAs with our base of over 1,000 customers. You can find our devices on satellites, exploratory spacecraft, and the international space station. Our detectors and LED emitters are emerging as a vital enabling technology for optical non-invasive medical diagnostics in many wearables and point-of-care devices for detecting diseased tissues, blood oxygen analysis, glucose monitoring, urinalysis, and other key biomarkers.With a history spanning almost 40 years, Marktech designs, tests, and manufactures components in New York, California, and Japan. We can deliver devices across the spectrum from 235nm to 4300nm for light emission (LEDs)  and from 250nm to 2600nm for photodetection (photodiodes). Marktech is a small company, but we have developed some world-changing technology over the years.Marktech’s core strengths include:

-- First, the ability to provide design and application engineering assistance to develop custom detectors and LED emitters meeting OEM specifications

-- Second, the capability to validate the performance of these new, custom parts in our extensive optical and electrical testing laboratories

-- Third, the prototyping and production facilities to produce these components in small to large production runs. Marktech often delivers custom optoelectronics for design projects that are too small or challenging for other LED and detector manufacturers.

These strategic competencies in engineering, application development, semiconductor manufacturing, package design and assembly, and, foremost, innovation were crucial factors behind the origin of the award-winning ATLAS packaged InGaAs detectors.

RELATED: Marktech Optoelectronics wins Best of Sensors 2023 for its ATLAS Hermetic SMD Packaged 2.6um InGasAs Photodiodes