EN
The semigroup $S = S(M₂(𝔽_{q}))$ of subspaces of the algebra $M₂(𝔽_{q})$ of 2 × 2 matrices over a finite field $𝔽_{q}$ is studied. The ideal structure of S, the regular 𝒥-classes of S and the structure of the complex semigroup algebra ℂ[S] are described.