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While GaN is a crucial semiconductor material for bright light‐emitting devices, fabrication of p‐type GaN remains challenging since the Mg acceptor commonly used for p‐type doping is not shallow enough. Doping of GaN with Be is a promising path, yet no reliable p‐type GaN has been achieved by Be doping so far. One of the reasons is a poor understanding of point defects in Be‐doped GaN that can be studied by photoluminescence (PL). The yellow (YL_Be) band at 2.15 eV is the dominant PL band in Be‐doped GaN. In this work, a blue PL band named the BL_Beband is discovered. It has a maximum at 2.6 eV and a lifetime of 0.8 μs at temperatures below 100 K. The BL_Beband is observed in GaN samples with relatively high concentrations of Be (>10¹⁸ cm⁻³). Both the YL_Beand BL_Bebands likely originate from the isolated Be_Gadefect, namely from electron transitions via the −/0 and 0/+ thermodynamic transition levels of the Be_Ga. The 0/+ transition level is located at 0.1–0.2 eV above the valence band. Other broad PL bands in Be‐doped GaN were also observed and preliminarily attributed to Be‐containing complexes. 

GaN samples are implanted with Be and F and annealed in different conditions to activate the Be_Gaacceptors. Photoluminescence spectra are studied to recognize the defects. The UVL_Beband with a maximum at 3.38 eV and the YL_Beband with a maximum at 2.15 eV are observed and associated with Be. The sequential implantation of Be and F ions into GaN at 600 °C reduces the concentration of nitrogen vacancies (V_N), as evidenced by the lack of the green luminescence band associated with the isolated nitrogen vacancy. First‐principles calculations are employed to find parameters of defects that can form after implantation. 

A systematic photoluminescence study of Be‐doped GaN grown by metal‐organic chemical vapor deposition is presented. All Be‐doped samples show the ultraviolet luminescence (UVL_Be) band with a maximum at 3.38 eV and the yellow luminescence (YL_Be) band with a maximum at ≈2.15 eV in GaN:Be having various concentrations of Be. The UVL_Beband is attributed to the shallow state of the Be_Gaacceptor with a delocalized hole. The YL_Beband is caused by a Be‐related defect, possibly the polaronic state of the Be_Gaacceptor with the charge transition level at 0.3 eV above the valence band. This broad band exhibits unusual properties. In particular, it always shows two steps in its thermal quenching. The second step atT ≈ 200 K is attributed to the emission of holes from the 0.3 eV level to the conduction band. The origin of the first step remains unexplained.