## 1 Introduction
In near space, the temperature sensor is also exposed to long-wave radiation from the upper and lower atmosphere and the main body of the radiosonde, which belongs to the environmental long-wave radiation. In addition, there is the thermal radiation of the sensor to the environment in the form of electromagnetic waves [15; 16; 17; 20; 21; 22]. Support structure heat conduction is the transfer of heat between the sensor and the supporting structure [15]. Temperature hysteresis: The sensor has a particular volume and a heat capacity. When there is a temperature difference from the outside world, the sensor generates stress and needs a certain amount of time to change to the outside temperature, which is called thermal hysteresis [23; 24; 25]. The primary temperature sensors for radiosonde are thermocouple sensors, bead thermistor temperature sensors, and platinum (Pt) thin film temperature sensors. Among them, the accuracy and linearity of thermocouple sensors are poor. As the most commonly used bead thermistor temperature sensor, it has low sensitivity and is susceptible to electromagnetic interference. The platinum thin film temperature sensor has the advantages of high sensitivity, small size, good stability, and high linearity. In terms of Pt thin film temperature sensor design, most of the existing Pt thin film temperature sensors have Pt deposited on a silicon or alumina substrate or have an adhesion layer added in between to increase the adhesion of the Pt [26; 27; 28; 29]. For example, [PERSON] et al. [29] evaluated electrical characteristics parameters such as resistance temperature coefficient, hysteresis, and measurement accuracy by preparing a temperature sensor with a Ti/Pt thin film layer. [PERSON] et al. [23] introduced a new processing technique for Pt thin film thermistors and verified the characteristics of Pt film thermistor models. [PERSON] et al. [30] obtained a thin film device with sufficient structural stability and adhesion by sputtering Pt films directly on the substrate and replacing the large-area Pt structure and passivation coating with an interconnected 10 \(\upmu\)m wide line. However, this structure still has a significant heat transfer phenomenon from the substrate and the adhesion layer to the Pt thin film, and the Pt thin film heat dissipation is poor. Additionally, there is no radiation-proof structure, resulting in large radiation errors. In terms of temperature error analysis, [PERSON] et al. [31] studied the variation in the self-heating effect with applied current, temperature, and different surroundings using a platinum resistance thermometer. [PERSON] et al. [32] proposed an e-type temperature sensor for high-altitude meteorology, using a 0.02 mm diameter platinum wire as a thermistor. They obtained the radiation temperature correction equation by fitting the simulation results. The uncertainty of solar radiation on temperature measurement was also explored by [PERSON] et al. [33] and [PERSON] et al. [34]. However, this literature only analyzed one of the errors, and their temperature error models do not match the temperature sensor designed in this paper. Therefore, the structural design and the corresponding temperature error analysis compensation are needed to achieve higher accuracy and temperature measurement performance when in situ temperature measurement is performed in near space. In addition, [PERSON] et al. [35] described how Shannon entropy can be applied to the stochastic analysis of MEMS to evaluate the performance and reliability of MEMS systems. In future research, we will introduce this method to improve the scientific nature of detection and data processing methods [36]. In this paper, by analyzing the source of temperature error, we optimize the sensor structure and the arrangement of sensors according to simulation and practical application and improve the temperature error model to realize high-precision in situ temperature detection in near space.