Blocking IR and transparent sub-THz and microwave filters

1 – Mylar film with AlN nano-structured layer,
2 – Teflon film with AlN nano-structured layer,
3 – Spectral radiant exitance at T = 300 K.

Sub-THz and microwave and sub-THz filters designed on  flexible polymer substrates to shield the influence of background IR radiation noise in sensitive low-temperature detectors. They can be applied for increase operation parameters of highly sensitive low-temperature detector assemblies in facilities like VLBI Global Observing Systems .

The technology developed of high thermal conductivity layers on flexible polymer substrates which are transparent in the sub-THz and microwave regions, secure high deposition rate and increased layer adhesion compared to other technologies. The filters developed provide quick heat withdrawal from their surface, due to high thermal conductivity of AlN layers (γ~320 W/m*K) used for deposition, therefore taking away the secondary reemission from their surface.

Filters transparency regions provide radiation transmission (~85-95 %) in wide microwave region 2-36 GHz (S, X, Ka bands) and within 60 to 280 GHz, sufficiently blocking (up to 83%) IR radiation in 5-25  mkm range (where about 82% of power density from the background is located) therefore diminishing the noise in low-temperature microwave or sub-THz detector systems and increasing their operational parameters.

Ukraine, Kiev. Contact persons: V. Korotash, [email protected]; Z. Tsybrii, [email protected]