FAQ

Q. Why MCT?
A. HgCdTe is the preferred material for producing infrared detectors due to its widely adjustable direct band-gap, high absorption coefficient, moderate thermal expansion and excellent electrical properties.
Q. What are "bulk MCT", "LPE MCT" and "MBE MCT"?
A. Bulk MCT is MCT through-and-through, cut from a solid MCT crystal. LPE stands for "Liquid Phase Epitaxy" and MBE stands for "Molecular Beam Epitaxy", methods for building a very thin layer of MCT on top of a substrate material. Epitaxial material has its advantages but is expensive and may not be the best option when Spitfire's bulk material is readily available. We suggest you check out bulk before opting for an Epi solution.
Q. Why bulk MCT?
A. Bulk MCT is proven technology in harsh environments and suitable for discrete sensors and low resolution arrays. Epi solutions are more suitable for high resolution imaging but are less robust when thermally cycled due to lattice mismatch (between the MCT and the substrate layer). Spitfire's high quality bulk MCT rivals Epi in applications where cost and reliability are paramount.
Q. Why NZ?
A. New Zealand is stable and business-friendly. We are high-tech, easy to communicate with and understand you and your customers. What's more, we work while you sleep!
Q. Why Spitfire?
A. In addition to "Why NZ", our company is independent - we exist to serve our customers. We think there are good reasons why you should talk to us if you are in already in, or contemplating being in, the IR industry and would like a quality partner to rely upon.
Q. What's the difference between a "wafer" and a "plank"?
A. In "Spitfire-speak" a wafer is a circular piece of MCT cut across (radially) the original cylindrical crystal. A plank is a rectangular piece of MCT cut "long-ways" (axially) from the original crystal. The standard finished thickness of both wafers and planks is around 0.50 mm. We choose to cut portions of our crystals as wafers or planks to get the best X characteristic (least variation) across each finished piece of MCT. Wafers and planks meet the same standards and neither is superior in performance to the other.
Q. What is a COT?
A. A COT is a "Certificate of Test" and is the document we use to present and certify the quality of each wafer we supply. We also call it a "map" because it shows contours of how X varies across the surface of the piece. COT examples and a more thorough explanation can be found here.
Q. What is X?
A. X is a measure of the composition of the crystal (as given by the formula Hg1-xCdxTe
and so denotes the CdTe fraction in the alloy. X predicts the infrared cut-on wavelength for a given operating temperature so is most useful when considering suitability for IR sensing applications. Our maps give an accurate picture of mean X and X variations across the surface of each piece of MCT we sell.
Q. What are 'mobility' and 'carrier concentration' ?
A. These are measures which determine device sensitivity and response time. Bulk MCT is typically superior to other materials when it comes to these key characteristics.
Q. Are there restrictions on the sale of MCT?
A. Yes. Historically MCT has been used in a range of applications that are subject to international treaties and control. Spitfire complies with these obligations and exports from New Zealand under permits issued by the Ministry of Foreign Affairs and Trade (MFAT). Depending on the country Spitfire is exporting to, you may be required to sign an "End Use Certificate" affirming that your application falls within allowable uses for MCT. Spitfire routinely obtains permits for complying end uses with few delays and at no cost to our customers. Please check with your local authorities regarding any import restrictions which may apply or contact us for further assistance.
Q. Can I discuss my project confidentially with Spitfire?
A. Customer confidentiality is paramount to us at Spitfire. We treat your IP with utmost care and will not discuss your business with anyone unless we receive your explicit permission. We are more than happy to sign a mutual non-disclosure agreement (NDA) with you to provide you the certainty that your ideas are safe with us.
Q. What is an MSDS?
A. An MSDS is a "Material Safety Data Sheet" which documents requirements for safely handling and processing a material. MCT is a relatively stable, unreactive material and can be safely stored and handled easily. An MSDS for MCT is available by contacting us.