Due to fabrication challenges in the past, previous InGaAs image sensors with extended spectral response—or extended InGaAs for short—had extremely high dark current and low signal-to-noise ratio because extended InGaAs requires a mismatched lattice of InGaAs and InP (Fig. 1), which lowers the quality of the film and increases the dark current. Also, the pixel pitch had size limitations and couldn’t be made smaller than a certain size. But due to improvements in the fabrication process and design capability, extended InGaAs image sensors now have lower dark current (Fig. 2) and smaller pixel pitch.
Figure 1. Lattice structure for standard InGaAs and extended InGaAs
Figure 2. Example of improved dark current for InGaAs image sensor with 2.6 µm cutoff wavelength
Thanks to improvements in the fabrication process, Hamamatsu now offers extended InGaAs image sensors with cutoff wavelengths ranging from 1.8 µm to 2.5 µm (Fig. 3). These extended InGaAs image sensors are alternatives to mercury cadmium telluride (HgCdTe or MCT) sensors, which have been often used to detect 1.7-2.5 µm wavelengths. Compared to HgCdTe, InGaAs is easier to handle because it is not as brittle as HgCdTe and doesn’t include any RoHS-restricted compounds such as mercury and cadmium. Also, extended InGaAs has better linearity and less cooling requirements. But the disadvantage of extended InGaAs sensors is that its bandwidth is not as broad as that of HgCdTe sensors.
Figure 3. Example spectral response ranges of extended InGaAs image sensors
Yes. Unlike silicon image sensors that could grow on CMOS, InGaAs image sensors are composed of an InGaAs photodiode array bonded or wired to a readout integrated circuit (ROIC). Therefore, Hamamatsu can combine multiple InGaAs photodiode arrays with different cutoff wavelengths on a single ROIC (Fig. 4). Please contact us to start a discussion about your customized image sensor.
Figure 4. Example of a customized InGaAs image sensor with multiple cutoff wavelengths on one ROIC
Albert Tu is a Marketing Engineer working on NIR/SWIR applications. He’s been helping customers find the right solution for their technology, and he’s developing new business by exploring potential technologies. Albert’s experience in high-tech industry and startups allows him to identify the need first and to find the right solution to solve it. Recently, he enjoys cooking in his spare time and likes to try out new recipes.
It looks like you're in the . If this is not your location, please select the correct region or country below.
You're headed to Hamamatsu Photonics website for US (English). If you want to view an other country's site, the optimized information will be provided by selecting options below.
For modern websites to work according to visitor’s expectations, they need to collect certain basic information about visitors. To do this, a site will create small text files which are placed on visitor’s devices (computer or mobile) - these files are known as cookies when you access a website. Cookies are used in order to make websites function and work efficiently. Cookies are uniquely assigned to each visitor and can only be read by a web server in the domain that issued the cookie to the visitor. Cookies cannot be used to run programs or deliver viruses to a visitor’s device.
Cookies do various jobs which make the visitor’s experience of the internet much smoother and more interactive. For instance, cookies are used to remember the visitor’s preferences on sites they visit often, to remember language preference and to help navigate between pages more efficiently. Much, though not all, of the data collected is anonymous, though some of it is designed to detect browsing patterns and approximate geographical location to improve the visitor experience.
Certain type of cookies may require the data subject’s consent before storing them on the computer.
This website uses two types of cookies:
There are two ways to manage cookie preferences.
If you wish to restrict or block web browser cookies which are set on your device then you can do this through your browser settings; the Help function within your browser should tell you how. Alternatively, you may wish to visit www.aboutcookies.org, which contains comprehensive information on how to do this on a wide variety of desktop browsers.
Occasionally, we may use internet tags (also known as action tags, single-pixel GIFs, clear GIFs, invisible GIFs and 1-by-1 GIFs) at this site and may deploy these tags/cookies through a third-party advertising partner or a web analytical service partner which may be located and store the respective information (including your IP-address) in a foreign country. These tags/cookies are placed on both online advertisements that bring users to this site and on different pages of this site. We use this technology to measure the visitors' responses to our sites and the effectiveness of our advertising campaigns (including how many times a page is opened and which information is consulted) as well as to evaluate your use of this website. The third-party partner or the web analytical service partner may be able to collect data about visitors to our and other sites because of these internet tags/cookies, may compose reports regarding the website’s activity for us and may provide further services which are related to the use of the website and the internet. They may provide such information to other parties if there is a legal requirement that they do so, or if they hire the other parties to process information on their behalf.
If you would like more information about web tags and cookies associated with on-line advertising or to opt-out of third-party collection of this information, please visit the Network Advertising Initiative website http://www.networkadvertising.org.
We use third-party cookies (such as Google Analytics) to track visitors on our website, to get reports about how visitors use the website and to inform, optimize and serve ads based on someone's past visits to our website.
You may opt-out of Google Analytics cookies by the websites provided by Google:
We inform you that in such case you will not be able to wholly use all functions of our website.