A temperature sensing apparatus and method are described to detect a change in a frequency due to a change in a temperature. An infrared light sensing apparatus and method are also provided. The temperature sensing apparatus may include an electrode to generate an electrical signal, a piezoelectric layer to convert the electrical signal into an acoustic wave, and a temperature sensitive layer formed by doping impurities in one or more structures formed on a substrate. Additionally, the infrared light sensing apparatus may convert into heat infrared light incident to an infrared light absorption layer, using an infrared light reflection layer and the infrared light absorption layer. A temperature sensitive layer may detect a change in a resonant frequency based on a change in a temperature of the heat, and may detect a change in infrared light based on the change in the resonant frequency.