A method for the manufacture of an electronic device comprising a double bank well-defining structure, which method comprises (a) providing an electronic substrate; (b) depositing a first insulating material on the substrate to form a first insulating layer; (c) depositing a second insulating material on the first insulating layer to form a second insulating layer; (d) removing a portion of the second insulating layer to expose a portion of the first insulating layer and form a second well-defining bank; (e) depositing a resist on the second insulating layer and on a portion of the exposed first insulating layer; (f) removing the portion of the first insulating layer not covered by the resist, to expose a portion of the electronic substrate and form a first well-defining bank within the second well-defining bank; and (g) removing the resist, wherein: a solution of a first organic semiconductive material is deposited into the first well-defining bank onto the electronic substrate and a solution of a second organic semiconductive material is deposited over the first organic semiconductive material and into the second well-defining bank; the deposition of the first organic semiconductive material results in a first pinning point with the first well-defining bank and the deposition of the second organic semiconductive material results in a different pinning point with the second well-defining bank; and steps (d) and (e) are performed prior to step (f) to prevent contamination of the electronic substrate when steps (d) and (e) are performed. (a) providing an electronic substrate; (b) depositing a first insulating material on the substrate to form a first insulating layer; (c) depositing a second insulating material on the first insulating layer to form a second insulating layer; (d) removing a portion of the second insulating layer to expose a portion of the first insulating layer and form a second well-defining bank; (e) depositing a resist on the second insulating layer and on a portion of the exposed first insulating layer; (f) removing the portion of the first insulating layer not covered by the resist, to expose a portion of the electronic substrate and form a first well-defining bank within the second well-defining bank; and (g) removing the resist, wherein: a solution of a first organic semiconductive material is deposited into the first well-defining bank onto the electronic substrate and a solution of a second organic semiconductive material is deposited over the first organic semiconductive material and into the second well-defining bank; the deposition of the first organic semiconductive material results in a first pinning point with the first well-defining bank and the deposition of the second organic semiconductive material results in a different pinning point with the second well-defining bank; and steps (d) and (e) are performed prior to step (f) to prevent contamination of the electronic substrate when steps (d) and (e) are performed. a solution of a first organic semiconductive material is deposited into the first well-defining bank onto the electronic substrate and a solution of a second organic semiconductive material is deposited over the first organic semiconductive material and into the second well-defining bank; the deposition of the first organic semiconductive material results in a first pinning point with the first well-defining bank and the deposition of the second organic semiconductive material results in a different pinning point with the second well-defining bank; and steps (d) and (e) are performed prior to step (f) to prevent contamination of the electronic substrate when steps (d) and (e) are performed.