Black Silicon(BSi) have been widely studied in recent years as a host for enhancement of material radiative properties [1, 2, 3, 4, 5, 6] for various applications. In particular, we have recently shown how high-level volume doped BSi can be an ideal candidate for infrared(IR) broadband absorbers and thermal emitters [7, 8]. In several applications, such as photovoltaics or infrared photodetectors, materials are doped at the surface rather than in the volume. On the other hand, many phenomena utilized for radiative properties engineering such are plasmonic effects or surface texturing are located at the materials surface. In addition, doping levels reachable with surface doping can exceed those commonly obtained with volume doping, i.e levels larger than 10 20 cm −3. For all these reasons, we focus in the present work on surface doped BSi fabricated using ion-implantation. Various fabrication processes, including sophisticated passivation techniques[9, 10], have been proposed to improve BSi absorptance. However, surface doping on non-periodic nano-structured surfaces like BSi has not been studied, hence the additional motivation to conduct this investigation. We have fabricated black silicon on 12 standard silicon wafers (n type doped with a doping level of the order of 10 −15 (cm −3) which have been subjected to various degrees of ion-implantation based on 3 principal parameters namely-the type of dopant(Boron or Phosphorous), ion beam energy(KeV), and implantation dosage(atm/cm 2). We observe that for n-type and p-type wafers of BSi, surface doping alone can be employed to achieve considerably enhanced radiative absorptance, with the flexibility of independent control of the dosage of dopants and depth distribution within 1-5 µm range of wavelength, but does not lead to lower absorption levels than volume highly-doped black silicon[7, 8]. In the case of surface doping, the dosage of ion-implantation is the dominant parameter in influencing its radiative properties. In the present work, the highest level of absorptance of 98.9% is obtained for wafers subjected to the highest phosphorous doping dosage of the order of 1 × 10 17 atm/cm 2. The doping concentration profiles are obtained for the different samples and enable the calculation of the threshold depth d, defined as the depth after which the ion-implanted BSi fails to retain the highest doping level of the order of 10 20 cm −3 (Fig. 1-b). The threshold depth is then compared to the penetration depth δ of electromagnetic radiation in the material. We observe that the highest dosage provides the highest threshold depth d. Only for samples where the dosage is of the order of 10 17 at/cm 2 and specifically in our case for n-type wafer doped with phosphorous, the condition for d = δ is fulfilled which leads to the highest levels of absorptance. Obtained results enable us to conclude that surface doped BSi can also be employed for IR applications requiring enhanced radiation absorptance such us IR photodetectors, solar thermal applications, solar photovoltaics and solar thermo-photovoltaics..