Fig. 1. (a) SEM image; (a1) AFM image of the exposed sample, (a2) magnified SEM image of developed sample; (b) corresponding cross-section curve; and (c) TEM cross-section image of AgGeSbTe heat-mode resist. For (a) and (b), the laser energy is 0.7 × 10³ mJ/cm². The gas flow ratio of CHF₃/O₂ is 60/2. The etching power is 200 W, and the chamber pressure is 50 mTorr with the time of 1 min. For (c), the laser energy is 1.2 × 10³ mJ/cm², and the etching time is 3 min.

Fig. 2. Dependence of (a) etching power, (b) developing time, and (c) laser power on linewidth and height of grating structures. For (a), the laser energy is 0.8 × 10³ mJ/cm². The gas flow ratio of CHF₃/O₂ is 60/2, and the chamber pressure is 50 mTorr with the time of 4 min. For (b), the laser energy is 0.7 × 10³ mJ/cm². The gas flow ratio of CHF₃/O₂ is 60/2, and the etching power is 200 W with the chamber pressure of 50 mTorr. For (c), the gas flow ratio of CHF₃/O₂ is 60/2, the etching power is 200 W, the chamber pressure is 50 mTorr, and the developing time is 3 min. The thickness of AgGeSbTe film is 250 nm.

Fig. 3. (a) Relationship between sheet resistance and temperature in AgGeSbTe thin film. (b) Thermal field distribution of heat-mode resist in thickness direction. (c) and (d) Temperature profiles in radius and thickness directions, respectively.

Fig. 4. (a) XRD patterns, (b) Raman data, and (c) XPS profiles of the as-deposited and laser-exposed AgGeSbTe films, where the exposed energy is 0.7 × 10³ mJ/cm².

Fig. 5. AFM cross-section profiles of (a) development, (b) etching of AgGeSbTe resist on Si substrate, and (c) etching of the pure Si, where the exposed energy is 1.2 × 10³ mJ/cm². For development of (a), the gas flow ratio of CHF₃/O₂ is 60/2. The etching power is 200 W, and the chamber pressure is 50 mTorr with the developing time of 3 min. Inset of (a) is SEM cross-section image of the developed sample. For Si etching of (b) and (c), the gas flow ratio of SF₆/Ar is 15/35. The etching power is 150 W, and the chamber pressure is 50 mTorr with the etching time of 5 min.