As others have have already asked, what is your definition of perfection? It's a big question, especially when you ask whether humans can create anything which is perfect.
It's useful to start with a little bit of etymology. "Perfection" comes from the Latin "perfectio" meaning "finished". But what does it mean for something to be finished? Things are what they are, but what does it mean for something to be "finished"? In fact, does it have any meaning at all?
Aristotle's answer revolves around the notions of finality or final causality. Aristotle distinguished living things from non-living things in that living things contain the cause of their own motion (or change) while other things do not, requiring an external cause to produce motion in them. Living things change in such a way that appears to lead towards something, a final end (telos), and so the motion of living things appears to be a realization of that finality and thus the acting of an organism in such a way as to reach perfection. Now while modern biology remains silent about finality, it is often the case that final cause is denied by many biologists because of philosophical developments that influenced the scientific revolution. If we deny finality, we must do away with any objective understanding of perfection as Aristotle understood it.
Your question concerns itself not with living things but with artifacts (unless you want to include genetic engineering, but it is not an important case deserving special treatment here, as I hope you'll see, by virtue of the above argument, and the one following). Here we must recognize the distinction between the different things that we mean when we use the word "creation", and they are: generation, mutation and creation. Briefly, generation is understood as begetting, giving birth, and so is the procreative act of life. Mutation is the changing of something, reordering preexisting matter into new forms and configurations. The final term, creation, something the Greeks did not understand because they understood the Universe to be eternal, is creation out of nothing ("creatio ex nihilo"). Clearly, then, the "creation" of artifacts is neither creation in the strict sense, nor is it generation. This leaves us with mutation. It conforms to our common sense notions: we take preexisting things and change them, refashioning them into new things.
Now since only living things have in themselves their final cause, and artifacts are the products of human action, it follows that the finality of an artifact must rest in the mind of the artist. The artist imposes a form, through his actions, on preexisting things in order to realize an end. I would argue that final causality cannot be imposed on a thing per se, but rather can be that which causes and orders actions in such a way that it produces something which conforms to it. Given that, the object can neither be perfect nor imperfect in itself but only in relation to the end in the mind of the artist. The questions now are: can an idea in the mind of an artist ever be perfect, or only an approximation? And, can a thing ever perfectly conform to that idea in the mind of an artist which we call the end? I argue that we only deal with approximations, which may be at least a partial consequence of our own imperfection.
"something perfect created by humans?"
seems like half of a question; Do you mean to say, "Is it possible for something perfect to be created by humans?" EDIT: just going to assume yes and fix the post. Feel free to revert if you think I misconstrued your question. That said, this is still rather non-constructive as a question. It seems like the only real answer is no if you are talking about actual (absolute) perfection, and if you are talking about anything less than it simply becomes a matter of how you want to define it...