Ultralow-Power and Miniaturized X‑ray Sensor Using the Single-Walled Carbon Nanotube Micro Network-Based Geiger Counter Design

• Published in: ACS applied electronic materials 2022-10, Vol.4 (10), p.4823-4830
• Main Authors: Kim, Hyehee, Li, Jianlin, Childress, Anthony, Seo, Juyeon, Bathalavaram, Poornaprakash, Busnaina, Ahmed, Moon, Sung-Hyun, Boo, Jihwan, Choi, Hak Soo, Kim, Geehyun, Kim, Young Lae, Jung, Yung Joon
• Format: Article
• Language: English
• ISSN: 2637-6113; 2637-6113
• DOI: 10.1021/acsaelm.2c00600

We present an ultralow-power, highly sensitive, and miniaturized X-ray sensor with micropatterned single-walled carbon nanotube (SWCNT) interdigitated networks inspired by the Geiger-Mueller counter design. Due to the unique nanostructured surface and superb electronic transport nature of assembled SWCNTs, a strong electric field is formed between and within highly organized SWCNT interdigitated electrodes, which effectively separates electrons and ionized ions created by incident X-rays into electrodes, facilitating electron detection. As a result, the device can detect a low X-ray dose rate (9.97 μGy·s–1) with an extremely low power consumption of 80–90 fW, demonstrating a sensitivity of up to 203.96 μC·Gy–1·cm–2. Furthermore, the interdigitated SWCNT electrode design produces a low noise level in the picoampere range, permitting exceptional real-time signal detection during X-ray exposure. These unique features of our SWCNT X-ray sensing device enable various low SWaP (size, weight, and power) radiation detectors in the fields of medicine, homeland security, and defense.