The problem I am faced with while playing a barre chord is that the finger i use to make the chord behind the finger that's barring has to be place very far from the fret so the sound it makes is always muttered.
Is there a way to avoid it ?
Although you are referring to barre chords (E Minor "shape", by the look of it), I think of this as being the classic "A-chord-problem".
Often, one of the first chords a guitarist will learn is A (finger 1, fret 2, string 4; finger 2, fret 2, string 3; finger 3, fret 2, string 2), and although this is quite a basic chord, and a simple shape, it is actually quite hard to play. Why? Because you have to squeeze all three fingers onto fret 2 on adjacent strings. So, it is really hard to get the first finger note to sound well, as it is further from the fret. You often have the same problem with the kind of barre chords you are playing here.
For your chord, you need to do two main things to make the third finger note sound as good as possible:
get the third finger as close to the fret as possible. You can do this by straightening it a little, so it "pushes" towards the fret. You can also get it closer to the fret by having it as close to the fourth finger as possible; these two fingers can be pressed together, with the third finger almost curved over the fourth finger, so that they almost work as one "unit". (This works well with finger three and four because finger three is just the right length to curve over the fourth finger.) You'll often also find it useful to move between barre chords keeping these two fingers locked together as a unit.
Apply a little more pressure with finger three than with finger four. You can help to do this by pushing your wrist forward just a little.
As I've got older, my fingers have got fatter - or the fingerboards have shrunk. So, with the 'A' shape in particular, at the nut end, I may use middle/ring/pinky, by 5 or 6 fet I've only put 2 fingers on strings 2,3 and 4, and by about the 9th fret, it's ring finger across 2,3 and 4. Yes, all 6 strings sound clear (I tend to barre bottom also), and it's a lot more comfortable.
It is hard to tell without seeing your whole hand and arm, but I would say that problem could be avoided by lifting the guitar neck as much as needed and repositioning your wrist. Many people tend to play with the wrist laid back and then the fingers seem to be not long enough. In particular folk and rock guitar players tend to play with the guitar neck lower than they should therefore limiting their reach and risking tendon injuries.
When playing chords that need wide stretches there are two main things that can help. First, most of the times finding the right position for your wrist and thumb (thumb might also be positioned too high or too close to your barring finger), and second stretching exercises.
One good stretching exercise I have been doing almost daily for many years is:
Position your left hand fingers
Play an ascending arpeggio once SLOWLY! (8th = 70 Beat per minute with your metronome)
Slide your index finger to the 10th fret and play an ascending arpeggio again
Slide your Middle finger to the 10th fret and play arpeggio again.
Slide ring finger to 11th fret and play arpeggio.
Slide pinky to 11th fret and play arpeggio.
Repeat the process moving one more fret to the left, and continue to do it until your index reaches the 8th fret, and then go back sliding your fingers to the right in reverse order. If at some point you feel like you are stretching too much then don't go that far. The 8th fret is normally a good initial limit unless your hands are too small.
Do this exercise a couple times a day. After a few weeks (I would say 8 to keep it on the safe side, although supervision of a trained teacher is advised) you can go to the 7th fret, but always being careful of not stretching too much, and not applying too much pressure on the fret board. Just enough to keep the notes sounding good and not even a tiny bit more. If it doesn't feel comfortable you are going too far.
You can progressively go lower, but I wouldn't recommend it without professional supervision. I normally don't go under the 5th fret.
One trick to reduce stress on your barring finger that could also help to increase your reach, is to place your barring finger on the strings in a way that your articulations fall on top of a string. If you choose to use mostly the fleshy part of your finger you will need more pressure, which will lead you to place your thumb closer to the barring finger.
Hope this helps. DP