界面活性劑於電化學沉積熱電材料之特性研究

Studies on electrochemical deposition characteristics of thermoelectric material with surfactant-added conditions

古耀方

指導教授 ： 楊啟榮

國立臺灣師範大學/科技學院/機電科技研究所/碩士(2007年)

摘要

本研究結合電化學沉積技術與界面活性劑的添加，電鑄n-type Bi-Te及p-type Sb-Te熱電材料，探討界面活性劑對於熱電材料鑄層及熱電特性之影響；發展利用熱電材料塊材取代傳統白金鈦網做為陽極，進行電化學沉積熱電材料。之後利用最佳之參數，搭配黃光微影製程，進行微型致冷晶片之製作。
在實驗之後驗證熱電材料塊材陽極比傳統白金鈦網陽極來的優異，係利用循環伏安法對離子濃度進行監測，發現熱電材料塊材陽極對於離子濃度有補充之作用，因此在長時間的電鑄，可使鑄層成份維持在正確的比例。
本實驗以7.5 × 10-3 M之Bi2O3與10 × 10-3 M之TeO2，7.5 × 10-3 M之Sb2O3與10 × 10-3 M之TeO2金屬粉末，搭配陰離子型界面活性劑MA，鑄出n-type Bi-Te及p-type Sb-Te熱電材料。Bi-Te材料在MA界面活性劑的使用之下，表面粗糙度由原先之40.51 nm大幅降低為15.42 nm，沉積速率由原先之4 ?m/hr提升至9 ?m/hr，並成功的將沉積之最小線寬降低至5 ?m。Sb-Te材料在界面活性劑MA的添加下，對於熱電特性有良好的改善效果，席貝克係數由原先之136.4 ?V/K提升至526.7 ?V/K，同時也成功將所電鑄之最小線寬降低至5 ?m。

關鍵字

熱電材料 ； 電化學沉積技術 ； 界面活性劑 ； 微型致冷器

並列摘要

The research represents electrochemical deposition technique with surfactant added to electroform n-type Bi-Te and p-type Sb-Te thermoelectric material. The effects of surfactant on electroformed film and thermoelectric characteristics were discussed in this thesis. Bulk thermoelectric material is used instead of Pt grid as anode for electroforming. Finally, better electroforming parameters were chosen for micro-cooler fabrication process.
For experiment result, it is demonstrated that bulk thermoelectric material anode is better than Pt grid anode. The ion concentration in electrolyte was monitored by cyclic voltammetry method. It was found that bulk thermoelectric material could supply extra ion to electrolyte. Thus, after a long-time electroforming process, the composition of electroformed film could be controlled correctly.
The concentration of Bi2O3, Sb2O3, and TeO2 metal powder was 7.5 × 10-3 M, 10 × 10-3 M, and 7.5 × 10-3 M, respectively. Anion surfactant, MA, was added in electrolyte to electroform thermoelectric material. In Bi-Te material, anion surfactant was added. The surface roughness decreased from 40.51 nm to 15.42 nm and deposition rate increased from 4 ?m/hr to 9 ?m/hr. The electroformed film could be completely deposited when the critical dimension was 5 ?m. In Sb-Te material, the thermoelectric characteristic could be improved and Seebeck coefficient increased from 136.4 ?V/K to 526.7 ?V/K and also completely deposited when the critical dimension was 5 ?m, too.

並列關鍵字

Thermoelectric material ； electrochemical deposition technology ； surfactant-added technique ； micro-cooler

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