Field of the Invention The present invention relates to an electronic device and, more particularly, to a p-GaN high-electron-mobility tran-sistor (HEMT) that can reduce gate leakage.

Description of the Related Art In response to the rapid development of technologies such as electric cars, base stations, and radio frequency commu-nication, the new generation of semiconductor devices needs to meet the requirements of high-power conversion, high-rate transmission, high bandwidth and low energy consump-tion. GaN has the characteristics of wide band gap, high breakdown voltage, high electron saturation velocity and good thermostability, and is accordingly an ideal semicon-ductor material. A high-electron-mobility transistor (HEMT) with GaN as the main material is a depletion-mode compo-nent that is conducted when no gate bias is applied, which poses a risk to safety in circuit application. Therefore, the GaN layer is doped in the conventional GaN-based HEMT to form a p-GaN layer, thus making the HEMT become an enhanced-mode element that capable of switching on or off by driving a gate. In order to effectively increase the energy band for enhancement, the conventional p-GaN HEMT will be highly doped to form a p+-GaN layer. However, in testing of reliability of the p+-GaN HEMT such as high temperature gate bias (HTGB) test and high temperature reverse bias (HTRB) test, as a result of an ohmic contact of the metal gate to the highly doped p+-GaN layer, hole tunneling occurs at the metal-semiconductor interface, resulting in severe leak-age current. In addition, due to the reverse bias, an extremely thin depletion region is formed between the highly doped p+-GaN layer and the AlGaN layer, causing direct tunneling of electrons, forming leakage current. Both of the foregoing tunnelings will cause the failure of transistor components. In light of the above, it is necessary to improve the conventional p-GaN HEMT. What is claimed is:

Field of the Invention The present invention relates to an electronic device and, more particularly, to a p-GaN high-electron-mobility tran-sistor (HEMT) that can reduce gate leakage.

Description of the Related Art In response to the rapid development of technologies such as electric cars, base stations, and radio frequency commu-nication, the new generation of semiconductor devices needs to meet the requirements of high-power conversion, high-rate transmission, high bandwidth and low energy consump-tion. GaN has the characteristics of wide band gap, high breakdown voltage, high electron saturation velocity and good thermostability, and is accordingly an ideal semicon-ductor material. A high-electron-mobility transistor (HEMT) with GaN as the main material is a depletion-mode compo-nent that is conducted when no gate bias is applied, which poses a risk to safety in circuit application. Therefore, the GaN layer is doped in the conventional GaN-based HEMT to form a p-GaN layer, thus making the HEMT become an enhanced-mode element that capable of switching on or off by driving a gate. In order to effectively increase the energy band for enhancement, the conventional p-GaN HEMT will be highly doped to form a p+-GaN layer. However, in testing of reliability of the p+-GaN HEMT such as high temperature gate bias (HTGB) test and high temperature reverse bias (HTRB) test, as a result of an ohmic contact of the metal gate to the highly doped p+-GaN layer, hole tunneling occurs at the metal-semiconductor interface, resulting in severe leak-age current. In addition, due to the reverse bias, an extremely thin depletion region is formed between the highly doped p+-GaN layer and the AlGaN layer, causing direct tunneling of electrons, forming leakage current. Both of the foregoing tunnelings will cause the failure of transistor components. In light of the above, it is necessary to improve the conventional p-GaN HEMT. What is claimed is:

Field of the Invention The present invention relates to an electronic device and, more particularly, to a p-GaN high-electron-mobility tran-sistor (HEMT) that can reduce gate leakage.

Description of the Related Art In response to the rapid development of technologies such as electric cars, base stations, and radio frequency commu-nication, the new generation of semiconductor devices needs to meet the requirements of high-power conversion, high-rate transmission, high bandwidth and low energy consump-tion. GaN has the characteristics of wide band gap, high breakdown voltage, high electron saturation velocity and good thermostability, and is accordingly an ideal semicon-ductor material. A high-electron-mobility transistor (HEMT) with GaN as the main material is a depletion-mode compo-nent that is conducted when no gate bias is applied, which poses a risk to safety in circuit application. Therefore, the GaN layer is doped in the conventional GaN-based HEMT to form a p-GaN layer, thus making the HEMT become an enhanced-mode element that capable of switching on or off by driving a gate. In order to effectively increase the energy band for enhancement, the conventional p-GaN HEMT will be highly doped to form a p+-GaN layer. However, in testing of reliability of the p+-GaN HEMT such as high temperature gate bias (HTGB) test and high temperature reverse bias (HTRB) test, as a result of an ohmic contact of the metal gate to the highly doped p+-GaN layer, hole tunneling occurs at the metal-semiconductor interface, resulting in severe leak-age current. In addition, due to the reverse bias, an extremely thin depletion region is formed between the highly doped p+-GaN layer and the AlGaN layer, causing direct tunneling of electrons, forming leakage current. Both of the foregoing tunnelings will cause the failure of transistor components. In light of the above, it is necessary to improve the conventional p-GaN HEMT. What is claimed is:

Field of the Invention The present invention relates to an electronic device and, more particularly, to a p-GaN high-electron-mobility tran-sistor (HEMT) that can reduce gate leakage.

Description of the Related Art In response to the rapid development of technologies such as electric cars, base stations, and radio frequency commu-nication, the new generation of semiconductor devices needs to meet the requirements of high-power conversion, high-rate transmission, high bandwidth and low energy consump-tion. GaN has the characteristics of wide band gap, high breakdown voltage, high electron saturation velocity and good thermostability, and is accordingly an ideal semicon-ductor material. A high-electron-mobility transistor (HEMT) with GaN as the main material is a depletion-mode compo-nent that is conducted when no gate bias is applied, which poses a risk to safety in circuit application. Therefore, the GaN layer is doped in the conventional GaN-based HEMT to form a p-GaN layer, thus making the HEMT become an enhanced-mode element that capable of switching on or off by driving a gate. In order to effectively increase the energy band for enhancement, the conventional p-GaN HEMT will be highly doped to form a p+-GaN layer. However, in testing of reliability of the p+-GaN HEMT such as high temperature gate bias (HTGB) test and high temperature reverse bias (HTRB) test, as a result of an ohmic contact of the metal gate to the highly doped p+-GaN layer, hole tunneling occurs at the metal-semiconductor interface, resulting in severe leak-age current. In addition, due to the reverse bias, an extremely thin depletion region is formed between the highly doped p+-GaN layer and the AlGaN layer, causing direct tunneling of electrons, forming leakage current. Both of the foregoing tunnelings will cause the failure of transistor components. In light of the above, it is necessary to improve the conventional p-GaN HEMT. What is claimed is: