| 摘要: | 氧化錫(SnOX)是一種可隨著氧濃度的變化可被製作成n/p MOS的通道材料，Sn4+的氧化物具有寬能隙且為理想的N型半導體，而Sn2+氧化物雖為p型，但因能隙偏窄(~0.7 eV)，故難以被整合到IC晶片裡。現今大多數對SnO是以該窄能隙相為基礎再發展，然而在2021年，以色列內蓋夫本-古里安大學的L.Nguyen等人研究發現SnO存在著特別的寬能隙(>1.1eV)相，但這些相並不穩定。為了穩定這些相，必須有額外的能量被加入。在這項工作中我們透過第一原理計算研究應力與尺寸效應對SnO寬能隙相的影響，經由分析不同晶相的自由能，我們得出M2(P21/c)、O2(Pbcm)、O3(Pmn21)是薄膜寬能隙相的最佳候選者。另外，我們也考慮了當SnO成長在氮化鈦(TiN)電極時產生的界面能影響，為實驗做出薄膜寬能隙SnO提供具方向性的成相預測。再者，我們施加額外的應力，加速薄膜生成寬能隙相的機率。為了保證寬能隙相能維持好的電性，我們計算自發型電洞缺陷(hole-killer)生成的機率，並以能帶校準的方式確認了這些寬能隙相是可作為p型摻雜使用。為了使該模型更具實用性，我們考慮這幾個重點相的溫度與壓力關係，使其能輔助製程上得到完好且高品質的寬能隙相。上述工作提供了在製程實驗上生成寬能隙PMOS所需的條件，且為氧化物半導體邏輯元件的製作開啟新的方法。;Tin oxide (SnOx) is a channel material that can be fabricated into n/p MOS structures depending on its oxygen concentration. The oxide of Sn4+ exhibits a wide bandgap and is an ideal N-type semiconductor, whereas Sn2+ oxide, although p-type, has a narrow bandgap (~0.7 eV), making it difficult to integrate into IC chips. Most current research on SnO is based on this narrow bandgap phase. However, in 2021, researchers, including L. Nguyen from Ben-Gurion University of the Negev, Israel, discovered a special wide bandgap phase of SnO (>1.1 eV). Still, these phases are unstable and require additional energy input for stabilization. In this work, we investigate the effects of stress and size on the wide bandgap phase of SnO through first-principles calculations. By analyzing the free energies of different crystal phases, we identify M2 (P21/c), O2 (Pbcm), and O3 (Pmn21) as the optimal candidates for the wide bandgap phase of thin films. Additionally, we consider the interface energy effects generated when SnO grows on titanium nitride (TiN) electrodes, providing directional phase predictions for wide bandgap SnO thin films for experimental purposes. Furthermore, we apply additional stress to accelerate the probability of thin film formation into the wide bandgap phase. To ensure good electrical properties of the wide bandgap phase, we calculate the probability of spontaneous hole-killer defect generation and confirm these wide bandgap phases as suitable for p-type doping through bandgap calibration. To enhance the practicality of the model, we consider the temperature and pressure relationships of these key phases to assist in achieving well-formed and high-quality wide bandgap phases during the fabrication process. This work provides insights into the conditions required for the experimental generation of wide bandgap PMOS and opens up new avenues for the fabrication of oxide semiconductor logic elements. |
