Vertical CdTe:PVP/<i>p</i>-Si-Based Temperature Sensor by Using Aluminum Anode Schottky Contact
H. G. Çetinkaya, Osman Çіçek, Ş. Altındal, Yosef Badalı, S. Demirezen
Abstract
The vertical Schottky barrier diode (SBD)-based temperature sensors with the drive modes are a significant issue with more advantageous than the on-chip sensor. The sensitivity ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${S}$ </tex-math></inline-formula> ) and the current conduction mechanisms (CCMs) of the vertical cadmium telluride (CdTe):polyvinyl pyrolidone (PVP)/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -Si SBD were studied experimentally over the range of 80–340 K and compared with that of the lateral and vertical sensors. It is shown that the low and moderated voltages of the CdTe:PVP/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -Si corresponding two linear regions of the current–voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}$ </tex-math></inline-formula> ) outputs are around 0.1–0.3 and 0.4–0.65 V, respectively. The variation of Schottky barrier height (BH; <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\sf \Phi } _{\text {Bo}}$ </tex-math></inline-formula> ) and ideality factor ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${n}$ </tex-math></inline-formula> ) with temperature was obtained according to two linear regions. Energy dispersion of the interface traps ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${N}_{\text {ss}}$ </tex-math></inline-formula> ) with changing temperature is additionally analyzed quantitatively. It is concluded that the thermionic-emission (TE) theory with double-Gaussian distribution (GD) is the dominant mechanism resulting the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}$ </tex-math></inline-formula> – <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}$ </tex-math></inline-formula> characteristics of the vertical CdTe:PVP/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${p}$ </tex-math></inline-formula> -Si SBD in this study. Moreover, in the constant current, the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${S}$ </tex-math></inline-formula> values at the drive current of 10, 20, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$50~\mu \text{A}$ </tex-math></inline-formula> were resulting in a range of −1.6 to −1.8 mV/K.