Applied Reseach & Photonics, Inc. (ARP) provides terahertz nano-scanning material characterization and testing services that helps semiconductor and nanomaterial researchers and manufacturers, easily visualize and identify in 3-Dimensional images, surface, sub-layer defects and failures. ARP testing is non-contact, non-distructive and performed at ambient temperatures.
ARP’s Terahertz Scanning Spectrometer (TeraSpectra) is a Terahertz Nano-Scanning Spectrometer/3D Imaging system that has two key technology innovations:
1) it breaks the spatial resolution limit of current generation optical inspection technologies, and
2) it uniquely identifies location and depth where defects exist.
Currently, there is no measurement technology that has the capability to provide an equivalent richness of information that ARP’s TeraSpectra system can deliver without damage or destruction of the test sample.
Atomic Force Microscopes (AFM) are one of the go-to technologies for wafer inspection, but require surface contact which can damage nanometer scale circuits. X-Ray inspection technology imparts high energies which can damage substrate lattice structure. IR inspection technologies at wavelengths of 1.5 microns and UV inspection at 256 nanometers, which are the current state of the art, but are limited to surface inspection only. Electron Microscopes are very expensive, require sample destruction and tedious sample preparation.
ARP consultants provide a comprehensive test report and assist in interpretation of results.
ARP is offering characterization services for just about any semiconductor wafers and nano-system. Quotation is provided on a case by case basis. Examples are available upon request.
Anis Rahman, PhD
Note: Overcoming the Abbe diffraction limit for high resolution imaging
Physics dictates that the ultimate image resolution is set by the wavelength of the light used for imaging – the so-called Abbe diffraction limit . In 1873 Ernst Abbe found that light with wavelength λ, traveling in a medium with refractive index and converging to a spot with half-angle q will make a spot with radius d = λ/(2n sin(q)), where, n sin(q) is called the numerical aperture (NA). Approximating NA = 1 (i.e., for vacuum), the lowest spot size (resolution) is λ/2.
Since the wavelength of electrons is much smaller than that of photons (2.5 pm at 200 keV), the resolution of an electron microscope is theoretically unlimited. In practice, the resolution of an electron microscope is limited to ~0.1 nm due to the objective lenses in the system. As such the electron microscopes (e.g., a TEM) and AFM seem to be the only option for nano-scale imaging.
While these techniques are effective and accurate, they are destructive; require tedious and time-consuming sample preparation. Additionally, they produce a frozen-in-time image of a single surface. A semiconductor wafer, for example, must be cut for inspection across its thickness. Samples may only be as big as it may fit in the sample chamber that must be kept under high vacuum.
Up until now, there was no alternative for nano-scale characterization of a whole wafer both on its surface and across its thickness or the sub-surface in a non-destructive mode with layer-by-layer inspection capability.
Applied Research & Photonics, Inc. (“ARP”) is a technology company in Harrisburg, PA, USA. ARP has developed terahertz nanoscanning instrument, providing the precision metrology required to measure critical, nanometer size surface and sub-surface features on today’s state of the art semiconductor chips. As these critical circuit dimensions are often smaller than a strand of human DNA, it is imperative that the measurements are made with a non-contacting probe which can accurately measure and graphically display such features of interest with a resolution of <1nm.
The semiconductor industry’s concern with current inspection technologies are: Surface contacting (Atomic Force Microscopes) can damage nanometer scale circuits; X-Ray inspection techniques impart high energies which can damage substrate lattice structures; UV inspection at wavelengths of 256 nanometers (the current state of the art) are limited to a device’s surface structure only and sub-surface defects are unobservable. Electron microscope measurements involve destructive and tedious sample preparation, and also impart high beam energies which can be detrimental to circuit structures. As such, semiconductor companies are seeking new technologies in response to these challenging measurement requirements. ARP has demonstrated its capabilities to answer the above mentioned needs. Its products are being used by industry and university research centers.
ARP is currently seeking funding for marketing its products and for formal introduction to the multi-billion-dollar global semiconductor manufacturing market. We propose a more formal presentation on our technology to the appropriate parties. Your evaluation of our proposal and advisement on funding would be greatly appreciated.
We invite your perusal of the following examples [2–4]. Additional examples are available up on request. Many thanks in advance for your consideration.