A functional CMOS compatible MEMS pyroelectric detector using 12%-doped scandium aluminum nitride

In this paper, we fabricate and demonstrate a functional complementary metal-oxide-semiconductor (CMOS) compatible pyroelectric uncooled thermal detector using 12% doped Scandium Aluminum Nitride (ScAlN) as the sensing layer. The ScAlN pyroelectric material is deposited at a temperature of ∼200 °C over an 8-in. wafer area. This detector has shown, in general, improved performance compared to AlN, with specific detectivity as high as ∼ 6.08 × 10 7 cm Hz / W and noise equivalent power as low as ∼ 8.85 × 10 - 10 W / Hz. The results show the specific detectivity of ScAlN-based pyroelectric detectors in the range of 107 cm Hz / W, which is an improvement compared to AlN-based pyroelectric detectors which report specific detectivity typically in the range of 105-106 cm Hz / W. This promising result opens up the opportunities for a CMOS compatible, 8-in. wafer-level manufacturable lead-free pyroelectric detector toward low cost and high throughput, allowing microelectromechanical systems (MEMS) and CMOS integration for increased applications in CMOS-MEMS integrated devices utilizing pyroelectric detectors.