中文摘要：

Ag基反射镜提高了薄膜型LED芯片的出光效率，但其易受破坏，通常选择抗腐蚀金属作为其保护材料，同时需要研究保护金属与p-GaN的接触性能，避免在p-GaN上同时形成两种欧姆接触引入的电流分流效应。通过传输线的方法研究了Pt，Cr，Ni／Ag与p-GaN的接触行为（在不同的合金条件），讨论了Cr和Pt作为保护材料的可行性。结果发现，N2中500℃合金后，NiAg／p—GaN的比接触电阻率（ρc）达到最低，ρc最低值为1．42×10^-3Ω·cm2；同条件下，80nmPt／p-GaN的ρc为6．63×10^-3Ω·cm2，30nmCr／p-GaN的P。为2．03×10^-2Ω·cm2，且其合金前的ρc为5．74×10^-2Ω·cm2，比合金后的ρc更高。这说明，Cr是更为理想的Ni／Ag保护材料，若Ni／Ag合金后再蒸Cr，效果更佳。最后，通过芯片老化实验，验证了Cr是一种较为理想的、可靠的反射镜保护材料，采用其制备的薄膜型功率芯片具有很高的可靠性。

英文摘要：

Ag-based reflector improves the light extraction efficiency of thin-film LED significantly, but it is easily damaged in pickling process, some corrosion resistant metals are usually chosen as protect material. Meanwhile, the contact characteristic between p-GaN and protect metal should be considered, In case of current diversion effect is caused by at least two similar ohmic contact existing on the p-GaN. By measuring the specific contact resistivity （ρc） between p-GaN and Pt, Cr, Ni/Ag by circular transmission line method （CTLM） in different alloy condition, the feasibility of Cr, Pt as the protect metal of Ag-based reflector was discussed. It is found that the pcof NiAg/p-GaN meets minimum （ρc = 1.42 ×10^-2Ω·cm2） when the sample is alloyed 1 minute in 500 ℃ N2 atmosphere. At the same condition, which of 80 nm Pt/p-GaN is 6. 63×10^-3Ω·cm2 and 30 nm Cr/p-GaN is 2. 03 ×10^-2Ω·cm2. In addition, the po of 30 nm Cr/p-GaN is 5.74 ×10^-2Ω·cm2 before the sample is alloyed. From above data, It can be concluded that Cr is the better protection material for Ni/Ag reflector, especially when the Cr layer evaporated after Ni/Ag is alloyed. Finally, the aging test was performed to demonstrate that Cr is an ideal and reliable mirror protection material and the thin-film chip integrated Cr protection material ofAg-based mirror has high reliability.