此篇論文將利用ISE-TCAD軟體作為模擬Bias Induced Color-tunable Emitters ( BICE )元件之工具。BICE為一由p-n-i-p-n所組成之結構，主要利用外加電壓極性不同，造成主動區內MQW ( Multiple quantum well )與SQW ( Single quantum well )收集載子量能力之差異，進而決定主發光波長。
一開始先從p-i-n結構著手，分別比較內含一組SQW或一組MQW其載子收集能力，從結果得知MQW結構在順偏下其載子收集能力較優於SQW結構。其後將p-i-n結構之主動區內含一組SQW與MQW，發現其主動區內能帶斜率會隨偏壓變化，當斜率在較陡時，其QW內載子收集能力將大為降低。並模擬一組SQW其井的寬度改變對其QW內之載子收集量影響，結果發現當井的寬度太小時將明顯降低收集載子能力。最後，於此結構模擬於照光下時，將可使能帶結構變為較平坦，進而增加QW內之載子收集能力。
最後進入BICE元件模擬，將分為雙端BICE元件與三端BICE元件，分由下列所述：
1. 雙端BICE元件：發現當未照光下，其元件不論偏壓在順逆偏壓下，其QW內載子收集量極少。而當光激發，產生大量電子電洞對可使能帶更平緩，有如等效順偏壓此接面。使電子與電洞能有效的進入此主動區，且在不同電場下被MQW和SQW作有效之收集是教人注目的。
2. 三端BICE元件：因偏壓不同分為Forward Active Mode和Reverse Active Mode。當元件工作於Forward Active Mode時，其SQW內載子收集量較大於MQW；相對偏壓於Reverse Active Mode時，其MQW內載子收集量較大於SQW。

In this dissertation, ISE-TCAD software is utilized as the simulation tool to study the carrier dynamics of Bias Induced Color-tunable Emitters ( BICE ). The structure of a BICE device is consisted of a p-n-i-p-n structure with one single quantum-well (SQW) and one set of multiple quantum-wells (MQW) inside the intrinsic active region. The carrier collection abilities for the MQW and SQW varied dramatically upon applying voltages across the designated electrodes, which leads to a higher carrier recombination rate through either MQW or SQW.
A p-i-n (PIN) structure with either one set of SQW or MQW inside the intrinsic region is analyzed. PIN with MQW exhibits a higher carrier collection ability compared to PIN with SQW under forward bias conditions. Another PIN structure with both SQW and MQW inside the active region is also analyzed. Both QWs exhibit lower carrier collection abilities when the slope of the band-edges become steeper under reverse bias. Results from simulation also reveal that the carrier collection abilities for a SQW are greatly affected by the well width. Reducing the well width decreases the collected carriers inside the SQW. Finally, the slope of the band-edges becomes flatter upon the illumination of light, which leads to higher carrier concentrations inside the quantum wells.
Two-terminal and three-terminal BICE are subsequently analyzed. The two-terminal BICE device exhibits poor carrier collection ability without light illumination no matter the biasing conditions. Simulation results reveal that the band-edge becomes flattened with light illumination, which leads to a dramatic improvement of carrier collection abilities for both the SQW and MQW. The biasing voltage across the device with illuminations can alter the carrier collection abilities for the SQW or the MQW. For the three-terminal BICE device, simulation results confirm that the existence of two different operation modes, Forward Active and Reverse Active Modes. SQW exhibits a higher carrier collection ability when the device is working in the Forward Active Mode. MQW exhibits a higher carrier collection ability when the device is working in the Reverse Active Mode.

參考文獻

[1] D. Zhang, F. E. Reed, T. Zhang,N. V. Edwards, and R. M. Kolbas ,” Two-terminal bias induced dual wavelength semiconductor light emitter” Appl. Phys. Lett. Volume 63, pp. 3367, 1993.

[2] F. E. Reed, D. Zhang, T. Zhang, and R. M. Kolbas , “Three-terminal bias induced dual wavelength semiconductor light emitter” Appl. Phys. Lett. Volume 65, Issue 5, pp. 570-572, 1994.

[3] Frederick E. Reed, ”The Development of Bias Induced Color-tunable Emitters (BICE)” PH. D. Dissertation, North Carolina State University, 1997.

[4] D. Zhang,” Optical Properties of Semiconductor Nanostructures and Devices”, PH. D. Dissertation, North Carolina State University,1993.

[5] Donald A. Neamen, 半導體物理元件。台商圖書，2003。

[6] 施敏，半導體元件物理與製程技術。國立交通大學出版社，2003。

[7] M. Grupen and K. Hess, “Simulation of Carrier Transport and Nonlinearities in Quantum Well Laser Diodes”, IEEE Journal of Quantum Electronics, vol. 34, no. 1, pp. 120–140, January, 1998.

[8] Wei_Luen Su and Yun_Chorng Chang,”Simulation Study of Bias
Induced Color-tunable Emitters (BICE)”, National Cheng Kung
University,2006.