Browsing by Author "DAI, BT"

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CHARACTERIZATION OF THE CHEMICAL-MECHANICAL POLISHING PROCESS-BASED ON NANOINDENTATION MEASUREMENT OF DIELECTRIC FILMS
(1995-09-01)
LIU, CW
;
DAI, BT
;
YEH, CF
;
電子工程學系及電子研究所
;
奈米中心
To better understand variations in the rate at which material is removed from a wafer during chemical-mechanical polishing (CMP), knowledge of the mechanical properties of the wafer surface is required. The nanoscale mechanical. properties of undoped dielectric films were investigated using the nanoindentation technique. Crack resistance examined from the loading curve suggested that precursor cracks for SiH4-atmospheric pressure chemical deposition films with a tensile stress, as compared with other dielectric films with compressive stresses, appeared in the earlier stage of indentation. The hardness of dielectric films determined from the unloading curve could be considerably dependent on the film's preparation methods. Correlation between the Si-O bond densities and hardness were also studied. Experimental results showed that there was a Linear relationship between the surface hardness and the removal rates of the undoped dielectric films under a well-controlled CMP process.
EFFECTS OF POLYSILICON ELECTRON-CYCLOTRON-RESONANCE ETCHING ON ELECTRICAL CHARACTERISTICS OF GATE OXIDES
(1995-05-01)
KANG, TK
;
UENG, SY
;
DAI, BT
;
CHEN, LP
;
CHENG, HC
In spite of the small amount of damage induced by Electron Cyclotron Resonance (ECR) etching, the radiation damage due to vacuum ultraviolet (VUV) photons from the high-density plasma still causes several problems. The leakage currents of the metal-oxide-semiconductor (MOS) capacitors with ECR-etched polysilicon gates are found to be higher than those of the control with wet etching. The leakage mechanism is therefore investigated in detail. The ions and radicals of the ECR plasma can directly attack the peripheral gate oxide and form the surface-damaged layer. In addition, the VUV photons will deeply impact the oxide interior and induce positive charges and interface trap states. ii dilute HF solution can effectively remove the surface damage layer. Annealing at 400 degrees C for 30 min can eliminate completely the positive charges. Furthermore, the SiO2/Si interface trap states are completely removed as the annealing time is raised to 60 min.
IMPROVEMENT OF THIN OXIDES THERMALLY GROWN ON THE REACTIVE-ION-ETCHED SILICON SUBSTRATES
(1995-05-01)
UENG, SY
;
WANG, PW
;
KANG, TK
;
CHAO, TS
;
CHEN, WH
Thin oxides thermally grown in reactive-ion-etched (RIE) silicon substrates in N2O and diluted O-2 ambient have been studied. The microroughness of the oxide-silicon interface was investigated using a spectrophotometer, atomic force microscopy (AFM), and cross-sectional high-resolution electron microscopy (HRTEM). The microroughness is strongly dependent on the RIE conditions and the post etching treatments. Furthermore, oxidation-enhanced interface microroughness has been observed. As compared with the pure oxides grown in diluted oxygen, N2O-grown oxides exhibit stronger immunity to RIE-induced damage. N2O oxidation of the etched specimens treated with an after-treatment-chamber (ATC) process result in the best electrical properties.