## 1 Introduction  
Radiation detectors are used in a variety of areas, including health, industry, and science. Ionizing radiation (X-and \(\gamma\)-ray) exposure may occur in these settings; therefore, proper radiation detection is critical for protecting the environment. The type of dosimeter used for a given application is determined by the energy range. Metal oxides are a well-known kind of substance utilized in dosimetry. It is concerned with the creation of particular structural flaws termed color centers as a result of radiation [1]. Metal oxide semiconductor field effect transistors (MOSFETs) might combine dose data and give an instant dose reading [2]. Because of its insensitivity to environmental conditions such as temperature and light, and even its flexibility extended gate, the extended-gate field-effect transistor (EGFET) structure has garnered greater attention in packaging and contact resistance. Furthermore, EGFETs may be utilized without exposing the metal oxide semiconductor field effect transistor (MOSFET) to irradiation, allowing it to be reused several times [3]. The EGFET design allows the MOSFET to be isolated from its biological or chemical surroundings. A sensing membrane is connected to the end of a signal line, which is connected to the MOSFET. Furthermore, by allowing the use of larger samples without being limited by the size of the MOSFET, this design gives a wider detection area [4]. Ionizing radiation dosimetry with irradiation sensor MOSFETs is dependent on translating the threshold voltage shift V\({}_{\text{TH}}\) into the absorbed dose D. This transition is caused by radiation-induced electron-hole pairs in the transistor's gate oxide layer, which leads to a rise in the density of interface traps and the accumulation of positive trapped charge. Extended gate field effect transistors (EGFETs) have adjustable sensitivity, rendering them ideal for a wide range of applications. Sensitivity, for example, can be adjusted by varying the thickness of the gate oxide layer [5,6]. Instead, transistors can be stacked in specific circumstances [7,8]. The sensitivity could also be adjusted by providing a positive bias to the gate while it is being irradiated [9]. Electric charges are produced and trapped inside the gate oxide layer (Qox,i) or even at the oxide-silicon interface (Qit,i) when a MOSFET is exposed to photons. When Qox,i is positive, the transfer characteristics I\({}_{\text{d}}\) (drain current) against V\({}_{\text{g}}\) (gate voltage) change towards negative voltages. The interface charges Qit,i mostly contribute to the deterioration of the carriers mobility p inside the channel, reducing the slope of the linear component of the characteristics [10]. The threshold voltage V\({}_{\text{TH}}\) is defined as the point at which the linear component of the curve intersects the V\({}_{\text{g}}\) axis and is provided by:  
\[\text{V}_{\text{TH}}\;=\;\text{V}_{\text{TH0}}\;-\;\frac{\text{Qox},\text{i}\;+ \;\text{Qit},\text{i}}{\text{Cox}}\;=\;\text{V}_{\text{TH0}}\;+\;\Delta\text{ V}_{\text{TH}} \tag{1}\]  
where V\({}_{\text{TH0}}\) is the pre-irradiation value of the V\({}_{\text{TH}}\) and Cox is the capacitance of the gate. The measurement of the change \(\Delta\)VTH of the threshold voltage after radiation allows the evaluation of the absorbed dose. Whenever the surface potential V\({}_{\text{s}}\) is equal to [PERSON]'s potential V\({}_{\text{F}}\) and [PERSON]'s level lies in the center of the semiconductor's energy gap, interface traps are neutral (overall charge equals zero), regardless of the dispersion throughout the semiconductor energy gap. The charge of FI simply causes the shift between two subthreshold properties toward this VG-axis, and the gate voltage that correlates to such surface potentials is designated as V\({}_{\text{MG}}\) (midgap voltage) and might even be calculated as the ordinate of the (V\({}_{\text{MG}}\), I\({}_{\text{MG}}\)) point at subthreshold features [11].