公开(公告)号：GB1220972A

公开(公告)日：1971-01-27

申请号：GB5050468

申请日：1968-10-24

Applicant: IBM

Inventor： KOSANKE KURT ,  KULCKE WERNER WOLFGANG ,  MAX ERHARD

IPC: G02F1/31

Abstract: 1,220,972. Light deflectors. INTERNATIONAL BUSINESS MACHINES CORP. 24 Oct., 1968 [18 Nov., 1967], No. 50504/68. Heading H4F. A light deflector comprises a switchable electro-optic half-wave plate 6, Fig. 2, selectively operable to change the plane of polarization of a linearly polarized light beam 1 by 90 degrees, and a deflecting element 40 constructed of a plurality of transparent layers, adjacent layers having different refractive indices, and positioned so that the light beam is incident at Brewster's angle and is thus transmitted through or reflected from the deflecting element depending on its plane of polarization. The reflected light beam is aligned with the original direction of the light beam by means of reflecting element 50. In the arrangement as shown in Fig. 2 including multi-layer deflecting elements 40-46, and reflecting elements 50, 56, by selectively energizing electro-optic half-wave crystals 6, 26 and 36 the light beam may be brought to any one of the positions 1f-1n. In a further arrangement, Fig. 3 (not shown) the deflecting elements 41 and 42, and the reflecting elements 51 and 52 of Fig. 2 each comprise one larger deflecting element and reflecting element, respectively. Each deflecting element comprises a ground glass plate having alternate 1 micron layers of titanium dioxide and silicon dioxide placed thereon. The reflecting elements may be curved.

公开(公告)号：CA895447A

公开(公告)日：1972-03-14

申请号：CA895447D

Applicant: IBM

Inventor： KOSANKE KURT ,  MAX ERHARD ,  KULCKE WERNER WOLFGANG

公开(公告)号：GB1134373A

公开(公告)日：1968-11-20

申请号：GB3329967

申请日：1967-07-20

Applicant: IBM

Inventor： KOSANKE KURT MAX ,  KULCKE WERNER WOLFGANG ,  MAX ERHARD

IPC: G02F1/31 ,  G03B15/00 ,  G03F9/00 ,  H01L21/00 ,  H01L21/68 ,  H03K17/78

Abstract: 1,134,373. Optical alignment apparatus. INTERNATIONAL BUSINESS MACHINES CORP. July 20, 1967 [July 21, 1966], No.33299/67. Heading G2J. Apparatus for optically aligning an object such as a semi-conductor wafer 1 with a reference mark 6 comprises an optical deflecting system 15, 16 which transmits a beam of radiation from a reflecting reference mark 5 on wafer 1 towards mark 6, control devices 18, 19 causing deflecting systems 15, 16 to scan the beam over the plane 17 containing mark 6 in accordance with a predetermined raster, a photo-cell 20 interrupting the scanning operation when the beam is incident on mark 6. Printed circuit patterns 22 are to be projected successively on to the photo-sensitized surface of wafer 1, and the wafer is first roughly aligned with the projection axis by screws 3, 4. The optical axis is then finally adjusted relative to the wafer using a subsidiary monochromatic light source 8 to which the wafer surface is insensitive, and a light switch 7. Light polarized at 11 passes via beam-splitter 12, lenses 13, 4 and devices 7, 15, 16 on to the area containing mark 5 and is reflected back through the system on to reference mark plane 17. When alignment of the projection axis is achieved, radiation from source 8 is cut off by switch 7 and the wafer is exposed to the pattern 22 which may be in hologram form using polarizing laser 24. Light switch 7 comprises an electro-optical crystal (31), Fig. 2 (not shown), to which a voltage (V) may be applied whereby the plane of polarization of a monochromatic light beam is rotated through 90 degrees, a birefringent plate (32) and a reflecting plate (33). Polarizer (34) passes light polarised in direction (41) only which is that of light beam (40) from source 8. Beam (44) from the laser is polarized at 90 degrees to direction (41) and is therefore only passed when crystal (31) is energized. Beams (40), (44) correspond to the extraordinary and ordinary beams for plate (32). Deflection units 15, 16 operating in X and Y directions are similar to switch 7 and comprise five electro-optical elements each followed by a birefringent element through which light may pass, depending on the state of the electro-optical elements, either as an ordinary or a deflected extraordinary beam. Each birefringent element is twice the thickness of its preceding element. The scanning deflections of the beam are obtained by activating the electro-optical elements in succession through five inter-connected bi-stable devices each with a switching frequency half that of the preceding device. The outputs of these devices are fed to the electro-optical elements through a logic circuit whereby each may be activated without affecting its neighbours. Rotational adjustment of wafer 1 is possible by using a Piezo-electric torsional support whereby the wafer may be rotated until moirÚ patterns due to lines on the wafer and reference mark reach a standard setting as sensed by photo-cells.