In the iButton temperature sensor, the physical location of the temperature sensor is in the middle of the iButton.
The circuit board and battery are closer to the side of the iButton with a flange and have a certain effect on the rate of heat conduction.
The side of the iButton without the flange has a relatively higher heat conduction efficiency.
Of course, both sides of the iButton can be used to measure temperature.
However, if the iButton is to be placed between two media, for example, half in soil and half exposed in air, and there is a large temperature difference between the soil and water, then we recommend placing the side of the iButton without the flange in the medium to be measured.