It is not permissible
to specify an area in the Masjid to bury the person who built it at his expense or any other person, because there are substantiated evidence indicating that it is not permissible to build Masjids on the graves. It is authentically narrated in the Two Sahih (authentic) Books of Hadith (i.e. Al-Bukhari and Muslim) on the authority of
`Aishah (may Allah be pleased with her) that
Um Salamah told Allah's Messenger (peace be upon him) about a church which she had seen in
Abyssinia (Ethiopia). She told him about the pictures which she had seen in it. He (peace be upon him) said: (Part No. 1; Page No. 425)
When any righteous pious man dies amongst them, they build a place of worship at his grave and put these pictures in it; they are the worst creatures in the sight of Allah.
is narrated by Ahl-ul-Sunan (authors of Hadith compilations classified by jurisprudential themes)
on the authority of
Ibn `Abbas (may Allah be pleased with them both):
Allah's Messenger (peace be upon him) cursed women who visit graves and those who build Masjids on them and place lights upon them.
There are other Sahih Hadiths (Hadiths that have been transmitted by people known for their uprightness and exactitude; free from eccentricity and blemish) reported from Allah's Messenger (peace be upon him) stating the same.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.