Blue Light Total Dose Nonvolatile Sensor Using Al-SOHOS Capacitor Device

The Al doped silicon–silicon oxide–hafnium oxide–silicon oxide–silicon capacitor device (hereafter Al-SOHOS) could be a candidate for blue light radiation total dose (hereafter TD) nonvolatile sensor. The UV radiation induces a significant increase in the threshold voltage V_T of the Al-SOHOS capacitor, and the change in V_T for Al-SOHOS capacitor also has a correlation to UV TD. The experimental results indicate that UV TD radiation-induced increase of V_T in Al-SOHOS capacitor under gate positive bias stress (hereafter PVS) is significant. Moreover, the V_T retention loss of the nonvolatile Al-SOHOS capacitor device after 10 years retention is good. The UV TD data can be permanently stored and accumulated in the non-volatile Al-SOHOS capacitor device. Furthermore, the UV TD data in the Al-SOHOS capacitor devices can be erased to original null state by opposite charges injection under gate negative bias stress (hereafter NVS). The Al-SOHOS capacitor device in this study has demonstrated the feasibility of non-volatile UV TD radiation sensing.