本文選題：硅薄膜　切入點(diǎn)：鍺薄膜　出處：《南京航空航天大學(xué)》2010年博士論文

【摘要】：硅基薄膜材料禁帶寬度可調(diào),光電性能良好,是第三代疊結(jié)太陽(yáng)電池材料的研究熱點(diǎn)之一。熱絲CVD法制備非晶硅、鍺硅等硅基薄膜性能相比于PECVD法制備的同類薄膜已表現(xiàn)出一定的優(yōu)勢(shì)。其在硅基薄膜材料及相關(guān)的太陽(yáng)電池制備領(lǐng)域的應(yīng)用前景越來(lái)越受到人們的重視。但作為一種新興方法,熱絲CVD法仍有較多規(guī)律和機(jī)理性問(wèn)題未能得到很好總結(jié)和解決。 本論文主要對(duì)熱絲CVD法制備硅基薄膜材料的工藝參數(shù)對(duì)所制備薄膜性能的影響規(guī)律進(jìn)行了研究和分析總結(jié),對(duì)與之相關(guān)的太陽(yáng)電池結(jié)構(gòu)進(jìn)行了模擬分析和優(yōu)化。 系統(tǒng)地研究了熱絲溫度、源氣體的流量比、沉積氣壓、襯底材料等對(duì)本征Si、p-Si和n-Si薄膜的結(jié)構(gòu)、光學(xué)及電學(xué)性能的影響規(guī)律,制備了性能滿足電池需要的非晶和微晶等不同結(jié)晶性的Si薄膜。在襯底溫度200℃條件下在Si(111)單晶襯底上得到了質(zhì)量近乎單晶的外延本征Si薄膜,并且制得了電阻率最低分別為0.036Ω·cm和0.064Ω·cm的高摻雜p-Si和n-Si薄膜。 制備硼摻雜p-Ge薄膜時(shí),發(fā)現(xiàn)隨著源氣體中B_2H_6摻雜比例增加,薄膜結(jié)晶性變差,Ge(220)擇優(yōu)取向增強(qiáng),薄膜導(dǎo)電性提高。隨著H_2稀釋比提高,薄膜的結(jié)晶性變好,但摻雜效果劣化。單晶硅襯底比玻璃襯底有利于薄膜晶化。在襯底溫度300℃條件下在單晶Si(100)襯底上制得了Raman峰位于300.3cm~(-1),結(jié)晶質(zhì)量較好的(220)取向的p-Ge薄膜。制備n-Si薄膜時(shí),發(fā)現(xiàn)PH_3摻雜比例提高和稀釋比降低都會(huì)使n-Ge薄膜的導(dǎo)電性劣化。制得了電阻率最低分別為0.024Ω·cm和0.10Ω·cm的高摻雜p-Ge和n-Ge薄膜。 對(duì)本征SiGe薄膜,隨著熱絲溫度的增加,薄膜的沉積速率幾乎線性增加。熱絲溫度的升高有利于Ge-Si鍵相對(duì)含量的增加,但對(duì)薄膜中的H鍵(Ge-H、Si-H等)相對(duì)含量無(wú)明顯影響。薄膜的禁帶寬度隨著熱絲溫度升高先增加后減小,在~24A時(shí)最大,為1.39eV。硅烷/鍺烷流量比(R_(S/G))的增加使薄膜中Ge-Si、Si-Si的相對(duì)含量均增加,但當(dāng)R_(S/G)1.4后Ge-Si鍵相對(duì)含量下降,Si-Si鍵相對(duì)含量顯著增大。隨著R_(S/G)的增大,Si-H的含量也有所增加。薄膜的禁帶寬度隨著R_(S/G)的增加滿足關(guān)系式E_g=0.19R_(S/G)+1.14。隨著稀釋比增加,薄膜沉積速率下降,薄膜結(jié)晶性變好,薄膜中SiH鍵相對(duì)含量增加,其它H鍵的相對(duì)含量下降,薄膜禁帶寬度減小。 根據(jù)半導(dǎo)體一維器件模型的特性參數(shù)方程組解得的太陽(yáng)電池電流密度、電壓及器件的結(jié)構(gòu)和性能參數(shù)的關(guān)系式,對(duì)硅基薄膜太陽(yáng)電池的結(jié)構(gòu)和各層膜性能對(duì)電池性能的影響規(guī)律進(jìn)行了模擬分析。結(jié)果表明:對(duì)于單結(jié)電池,摻雜層的厚度越薄電池性能越好,但不能低于形成穩(wěn)定空間電荷區(qū)所必需的最小厚度;為了得到最優(yōu)電池效率,i-厚度和p-和n-摻雜濃度均有一合理取值范圍,超出該范圍電池性能劣化,具體的取值范圍因材料而異。 對(duì)上下子電池均為pin結(jié)構(gòu)的雙疊結(jié)太陽(yáng)電池的模擬研究表明:上下子電池禁帶寬度匹配對(duì)電池性能的優(yōu)化很重要。不同材料構(gòu)成的雙疊結(jié)太陽(yáng)電池的性能比對(duì)應(yīng)的任一材料構(gòu)成的相同厚度的單結(jié)電池的性能明顯提高;同種材料構(gòu)成上下子電池的疊結(jié)太陽(yáng)電池比厚度相同的單結(jié)電池的填充因子、轉(zhuǎn)換效率也略有提高。實(shí)驗(yàn)研究也驗(yàn)證了疊結(jié)結(jié)構(gòu)有利于提高電池性能的結(jié)論。對(duì)n~+p~-結(jié)構(gòu)的單結(jié)SiC電池和SiC/poly-Si疊結(jié)太陽(yáng)電池的初步模擬分析研究表明,在一定范圍內(nèi)提高p~-層摻雜濃度,有利于減少p~-層的厚度,在電池生產(chǎn)時(shí)可以減少沉積時(shí)間,提高生產(chǎn)效率,降低成本。
[Abstract]:The silicon - based thin - film material has the advantages of adjustable band width and good photoelectric performance , which is one of the hot spots of the third generation of laminated solar cell materials . Compared with the similar thin film prepared by PECVD method , the silicon - based thin film has certain advantages compared with the similar thin film prepared by the PECVD method .

In this paper , the influence of the process parameters on the properties of thin films prepared by hot filament CVD was studied and summarized , and the solar cell structure related to it was simulated and analyzed .

The structure , optical and electrical properties of intrinsic Si , p - Si and n - Si films were studied systematically . The effects of the structure , optical and electrical properties of Si , p - Si and n - Si films on Si , p - Si and n - Si films were studied systematically .

In the preparation of boron - doped p - Ge films , it was found that the crystallinity of the films increased with the increase of the doping ratio of B _ 2H _ 6 in the source gas . The crystallinity of the films was improved . The crystallinity of the films was improved with the increase of the dilution ratio of H _ 2 .

With the increase of R _ ( S / G ) , the relative content of Ge - Si and Si - Si in the films increased , but the relative content of Si - Si bonds increased with the increase of R _ ( S / G ) .

In order to get the optimum cell efficiency , the i - thickness and the p - and n - doping concentration have a reasonable value range , which is beyond the range of battery performance , and the specific value range varies depending on the material .

The simulation results of double laminated solar cells with pin structure for both upper and lower sub - cells show that the performance of single - junction solar cells with the same thickness is obviously higher than that of single - junction cells with the same thickness . The results show that the stacking structure is beneficial to improve the performance of cells . The experimental study also proves that the stacked structure is beneficial to improve the performance of the battery .

【學(xué)位授予單位】：南京航空航天大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2010
【分類號(hào)】：TM914.42

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 方茹;基于納米硅鋁誘導(dǎo)的多晶硅薄膜制備與性能研究[D];南京航空航天大學(xué);2012年

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本文編號(hào)：1710852