Nov 3 2012
Alacron, Inc., makers of high performance frame grabbers and accelerated frame grabber subsystems for more than 25 years, has announced back side imaging camera (BSI). Among the many markets and applications that will find Alacron’s new technology useful is the semiconductor industry, where Alacron’s BSI offers better, faster and more financially efficient wafer inspection.
The BSI camera will also be of interest to those within the medical, aeronautics, military, and other manufacturing industries, wherever spectral extremes such as deep ultraviolet (DUV) and high energy tolerance is needed.
Back side imaging is performed by applying the light to the side opposite the electronic of the sensor. Typically the sensor is thinned so the drift path of the generated photoelectrons is as short as possible.
Alacron’s BSI camera offers the following advantages:
- 100 % fill factor
- Improved QE over a wide spectral bandwidth (e.g. DUV to NIR)
- Reduced Dark Current
- Extreme energy saturation tolerance
In developing the new technology, Alacron collaborated with individuals at JPL’s (Jet Propulsion Laboratory) Micro-devices Laboratory.
“Delta doping is a process by which a large surface potential is created to direct photoelectrons generated at the surface toward the photo diodes of an imaging array,” says Dr. Joseph Sgro, CEO of Alacron, Inc. “The penetration depth of (UV) photons into silicon is several nanometers. Photoelectrons generated by (UV) photons recombine without propagating to the photo diodes in the absence of passivation because they are trapped near the surface. In addition the photodiodes experience a lateral capture effects in BSI applications, effectively increasing the fill factor to 100% in such applications.”
Sgro adds that the antireflective (AR) coatings are applied to the sensor to reduce the loss of photons due to reflection of the bare silicon surface. Over fifty percent of the photons usually are lost to reflection in the absence of AR coatings. AR coatings can be designed for specific wave lengths. For example, an AR coating for 263 nm can improve transmission to above 90 percent, and above 80 percent for 193 nm.
Launched by Dr. Sgro in 1985, Alacron is known internationally for its innovative product designs and high quality manufacturing. Its product family of frame grabbers, high speed visual imaging cameras and related subsystems, analytical tools, along with customized hardware, software and integration middleware are deployed worldwide. Alacron’s digital imaging products are used by engineers in many fields, including aerospace, medicine, manufacturing, and defense. All Alacron customers benefit from the highest quality products that also boast the kind of performance and durability required by robotic, surveillance, and other machine vision applications.
“Dr. Sgro’s background and on-going interest in neurology and advanced mathematics, gives him a unique insight into R&D and manufacturer of products that address real world demands for integrated design and the need for highest quality products,” said Paul Stanton, head engineer at Alacron. “Dr. Sgro’s collaboration with JPL has resulted in improved DD and AR processes, providing users with a technology which has real advantages in crucial global markets such as medical, military and manufacturing, particularly within the semiconductor industry.”