With raptors, 'taming' isn't straight forward. There are benefits to the bird in getting it used to being close to it's carer while it is in captivity. Note, though, that taming or manning is what happens in full grown raptors, and is nothing to do with the imprinting and socialisation that happens with chicks.
As a group, raptors are a pretty high strung bunch. They are easily frightened and stressed by everything they encounter in captivity. This kind of stress works against the healing the bird needs to do. In many cases, it is a good idea to sit near the patient, let it see you bring it food, and generally get used to your daily routine. Raptors, like all animals like a routine that is predictable. Even when you are in a hurry or stressed, you must make yourself calm and go slow when working with a bird. Talking quietly and avoiding a direct stare at the raptor can also make you seem less threatening.
This basic type of taming is known as 'manning'. This is an old term that means getting the raptor used to people and their surroundings. Many of my patients have learnt to step onto a gloved hand for removal from a hospital box, and weighing while they sit on the scales on top. Once the box is cleaned, they can be persuaded to get back on the glove to go back in. While this takes extra time on my part, and may be initially a bit more stressful (because of spending more time with me), it is much less stressful in the longer term. Raptors find being grabbed very offensive and distressing, and do not get used to it.
Raptors that are going to be recovering for an extended period can be brought a step further in manning by offering them food when they are sitting on a gloved hand. Some birds are more comfortable with this than others. With those that don't start to settle in your presence, the opposite approach is best- leave them alone as much as possible, and avoid letting them see human activity except for your feeding and cleaning chores. Some raptors will start to even look forward to seeing you, and you can give them some behavioural enrichment. This is especially good for longer term birds that get sick of being in a box and want out, but can't be put in a larger enclosure yet because of their injuries. They can be encouraged to hop to the glove or to different perches in the room, and this is a tremendous release from boredom. A few minutes of this seems to get some birds to relax and settle in their hospital box much better.
Being more comfortable with people means the raptor will be less likely to panic when it sees people enter a larger outdoor enclosure to feed or clean. The more space they are given, and less human contact, the more un-used to people they become. The effects of manning will start to disappear as soon as you stop associating with the raptor, and as soon as it has enough space to choose to leave your presence. Your association with food will also be forgotten by the adult bird as soon as it gets lots to eat out in an aviary. Given that any bird that has been in long enough to be well manned will have a long recovery in a flight pen, what you will be releasing is an un-manned, wild bird.