标题: 使用低压化学气相沉积法成长氧化钽薄膜
Low Pressure Chemical Vapor Deposition of tantalum Oxide Thin Films
作者: 汪俊男
Wang,Chun-nan
裘性天
Chiu,Hsien-Tien
应用化学系硕博士班
关键字: 化学气相沉积;氧化钽;高介电;有机金属;CVD;atantalum oxide;high dielectric;metalorganic
公开日期: 1996
摘要: 本论文是以tert-butylimdotris (diethylamido)tantalum为前驱物在通水气 (0~1.2 mg/min)及氧气 (200 sccm)下分别以673-873 K以及573-873 K下成长氧化钽薄膜.并在大气压力下通氧气以1123 K做事后的回火处理. 并使用了SEM, AFM, AES, ESCA, XRD, RGA,GC/MS鉴定薄膜的组成及型态. 在回火前通水气可得到颗粒状的薄膜, 而通氧气沉积的薄膜则为柱状. 回火后薄膜有收缩现象, 且颗粒皆变大. 在不通水气下有26-40A/min的成长速率, 通水气的成长速率则在4-8.4 A/min, 通氧气的成长速率略高于通水气下的成长速率. 由AFM亦发现回火后粗糙度增加. 由AES对回火前的薄膜做纵深分布发现氧钽在膜内分布均匀且碳并未深入里层. 结晶性方面回火前皆没有结晶性. 回火后可得到 b-Ta2O5的X-ray绕射图.即使是不通水气的状况下所成长的薄膜在经回火后也呈现相同的情形. 由RGA分析反应可发现到Me2C=CH2, CH3CN, Et2NH, 以及H2. 而由GC/MS也发现HONEt2. 为了更进一步了解所沉积的薄膜的电性, 也测量了在873 K下通氧气沉积的薄膜不经回火及分别经过30, 60分钟回火的C-V及I-V图. 可发现漏电流在回火后被抑制在2x10-8 A/cm2.在回火30分钟时其崩溃电压3.0 MV/cm, 介电常数则为22. 回火60分钟后的介电常数则有35.-
A procedure is studied to produce tantalum oxide thin films. The deposition uses tert-butylimidotris (diethylamido)tantalum in the presence of water vapor (0-1.64 mg/min) and oxygen gas (200 sccm) under the temperature 673-873 K and 573-873 K, respectively. Post annealing is employed under atmosphere oxygen at 1123 K. SEM, AFM, AES, ESCA, XRD, RGA, GC/MS are used to characterize the thinfilms. Grain size ranging from 30-60 nm are observedwhen deposited with H2O. Columnar grains are found when deposited with oxygen.Films are shrunk and rougher after annealing. Growth rates of the films grownwithout water vapor are 26-40 A/min* while the growth rate of films grown withH2O and O2 are 4-8.4 A/minand 10 A/min, respectively. Distribution of tantalumand oxygen is uniform in the film as indicated by AES. Films are amorphous before annealing and crystallized into b-Ta2O5 after annealing. With RGA andGC/MS,H2C=CMe2, CH3CN, Et2NH, H2 and HONEt2 are found in the deposition. Electrical properties of the films grown with oxygen are also measured. Leakagecurrent are suppressed to 2x10-8 A/cm2 after annealed for 30 min. Breakdownvoltage is 3 MV/cm. Dielectric constant of anneal 30 min and 60 min are 22 and 35, respectively
URI: http://140.113.39.130/cdrfb3/record/nctu/#NT850500001
http://hdl.handle.net/11536/62230
显示于类别:Thesis