DC 欄位 |
值 |
語言 |
DC.contributor | 物理學系 | zh_TW |
DC.creator | 李明倫 | zh_TW |
DC.creator | Min-Lum Lee | en_US |
dc.date.accessioned | 2002-7-2T07:39:07Z | |
dc.date.available | 2002-7-2T07:39:07Z | |
dc.date.issued | 2002 | |
dc.identifier.uri | http://ir.lib.ncu.edu.tw:444/thesis/view_etd.asp?URN=89222016 | |
dc.contributor.department | 物理學系 | zh_TW |
DC.description | 國立中央大學 | zh_TW |
DC.description | National Central University | en_US |
dc.description.abstract | 摘 要
本實驗是在p型氮化鎵中佈植矽離子,經由氮氣環境下的快速熱退火處理而形成矽離子佈植試片。X-Ray布拉格繞射結果顯示,即使經由1150oC, 60秒快速熱退火處理,仍然無法將結構完全修復。藉由改變離子佈植及熱退火的條件可以將試片的電性由p型(~3´1017cm-3)轉變為n型(2´1017cm-3~2´1019cm-3)。本實驗發現矽原子在典型的矽離子佈植試片中,其活化能(~10 meV以下)比磊晶成長的矽摻雜試片(~15 meV以下)低,且多了一個深層能階(~60 meV)的施體。在光激發光譜的分析中,觀察到一個372nm峰值,它可能是由離子佈植所造成的結構破壞而引發的;另外,還觀察到一個525nm峰值,它可能源自跟磊晶成長式的矽摻雜n型氮化鎵所具有之黃光峰值一樣。
矽離子佈植式p-n二極體的特性分析中,在小的順向操作偏壓(Vj<2V)時,除了單純的複合電流與擴散電流之外,還存在一些由缺陷所造成的額外傳導電流,而這些缺陷的來源有可能是成長時的空缺或錯位,以及離子佈植所造成的結構破壞。在電激發光譜的分析中,觀察到一個430nm峰值,它可能是來自於和鎂有關的受體和未知施體之間的躍遷。另一方面,矽離子佈植式p-n二極體應用在逆向偏壓的操作範圍時,可以當作一個紫外光光檢測器。當外加的逆向壓在1V時,暗電流是50 nA/cm2,而當外加的逆向壓在3V時,暗電流是1.5 A/cm2。這個光檢測器的截止波長大約是365 nm(光響應強度約為 0.33 mA/W),且對紫外光(~365 nm)和可見光(~500 nm)的鑑別度可達260倍。 | zh_TW |
dc.description.abstract | Abstract
Si ion implantation into p-type GaN followed by rapid thermal annealing (RTA) in N2 has been performed. X-ray diffraction analyses indicated that ion-implanted damage remains even with 1150oC, 60sec RTA. By varying implantation and post-implantation annealing conditions, we could convert carrier concentration from p-type 3´1017cm-3 into n-type 2´1017cm-3~2´1019cm-3. It was found that typical activation energies of Si implants in p-GaN are lower than 10 meV Such activation energies are smaller than those observed from epitaxially grown Si-doped GaN films (~15meV). A deep donor level with activation energy of 60meV was also found from some samples. Photoluminescence (PL) studies show that the peak appears at 372nm might be related to implantation-induced defects. A green emission band was observed from Si-implanted GaN. This green emission may be related to the yellow band observed for the epitaxially grown Si-doped GaN.
Characterizations of GaN n+-p junction diodes formed by Si implantation into p-GaN were also performed by using various techniques including current-voltage(I-V) measurements and electroluminescence(EL) spectroscopy. The current-voltage characteristics at low forward bias region (Vj<2 V) are measured. It might be interpreted as the results are governed by a trap-assisted generation-recombination mechanism rather than a simple recombination current. In addition to the grow-in defects including vacancies(VGa VN) and dislocation, ion implantation would further induce more defects or unrecoverable structural damage in the implanted layers, which these are the source of possible trap-assisted generation-recombination centers, and affect significantly the characteristics of optical and electrical properties. For EL measurements, a blue band emission around 430 nm was observed, which can be attributed to a Mg-related donor-to-acceptor transition. On the other hand, for the application in visible blind UV detector, the Si-implanted planar GaN p-n diodes are also a potential candidate. The current density measured under dark condition is around 1.5 mA/cm2 and 50 nA/cm2 at a reverse bias of 3 V and 1V, respectively. Spectra response measurements revealed a cut-off wavelength of about 365 nm and a peak responsivity of around 0.33 mA/W at 365 nm. In addition, the photodiodes showed a typical visible rejection ratio, which divides the values of the responsivity at 365 nm and at 500 nm, of around 260. | en_US |
DC.subject | 矽離子佈植 | zh_TW |
DC.subject | Si-implanted | en_US |
DC.title | 矽離子佈植在P型氮化鎵的材料分析與
元件特性之研究 | zh_TW |
dc.language.iso | zh-TW | zh-TW |
DC.title | Material Characterizations and DeviceApplications of Si-implanted p-GaN
| en_US |
DC.type | 博碩士論文 | zh_TW |
DC.type | thesis | en_US |
DC.publisher | National Central University | en_US |