Imaging or exposure device, in particular for making an electronic microcircuit
View Patent ↗The imaging or exposure device comprises a radiation source ( 1 ), a reticle ( 3 ) mounted between the radiation source and an optical projection system ( 4 ) for shaping the radiation downstream from the reticle ( 3 ), the optical projection system ( 4 ) comprising a series of mirrors ( 7, 8, 10, 11 ) including at least two mirrors ( 10, 11 ) that are deformable, having deformer members ( 12, 13 ) connected to a control unit ( 14 ) associated with an image analyzer ( 15 ) to deform the two deformable mirrors in separate manner, firstly as a function of differences relative to an image quality setpoint, and second as a function of differences relative to an image distortion setpoint.
1. An imaging or exposure device comprising a radiation source ( 1 ) emitting radiation ( 2 ), a reticle ( 3 ) mounted between the radiation source and an optical projection system ( 4 ) for shaping the radiation downstream from the reticle ( 3 ), the optical projection system ( 4 ) comprising a series of mirrors ( 7 , 8 , 10 , 11 ) for making an image ( 5 ) of the reticle ( 3 ), a plurality of mirrors ( 10 , 11 ) of the optical projection system ( 4 ) being deformable mirrors including deformer members ( 12 , 13 ) connected to a control unit ( 14 ), the device being characterized in that the number of deformable mirrors is strictly limited to two, the control unit being associated with an image analyzer ( 15 ) to deform one of the deformable mirrors ( 10 ) mainly as a function of differences relative to an image quality setpoint, and to deform the other deformable mirror mainly as a function of differences relative to an image distortion setpoint.
2. A device according to claim 1 , characterized in that one of the deformable mirrors ( 10 ) is located at the pupil of the optical projection system ( 4 ), and the corresponding deformer members ( 12 ) are controlled mainly as a function of the image quality setpoint, the other deformable mirror ( 10 ) being an intermediate mirror between the pupil of the optical projection system and the image ( 5 ) and being controlled mainly as a function of the image distortion setpoint.
3. A device according to claim 2 , characterized in that the intermediate deformable mirror ( 11 ) is disposed immediately upstream of the image ( 5 ).
4. A device according to claim 1 , characterized in that the deformer members ( 12 , 13 ) are controlled at a rate of less than 1 Hz.