SU600562A1 - Digital machine for control of electron beam microprocessing - Google Patents

Description

one

The invention relates to computing technology and can be used for the automated control of the production processes of integrated circuits based on electronic technology.

A known digital machine for controlling electron beam microprocessing processes comprising a control device, a transmitter unit, a memory device, a control unit, a buffer memory device, an operation unit connected to the code bus and control signals buses, a coordinate control unit connected to the block of operations, inputs and outputs of the machine, the block of combining the axes of the axes connected to the code bus, to the block of operations, to the outputs of the machine, the deviation block, block angular transformations, images, connected to the code bus and to the output of the block combining the coordinate axes and the input of the deviation block

one.

This machine allows reproducing patterns of complex integrated circuits.

The prototype of the invention is a digital machine for controlling electron beam microprocessing processes, comprising a transmitter unit, a memory device, a control unit, a buffer memory device, a computing unit connected to the code bus and control signal buses, a communication unit with a control object, an input and the output of which is connected to the output and input of the computing unit, the input and output of the maschion are connected to the corresponding input and output of the communication unit with the control object.

The structure of the communication unit with the control object includes devices for correction, control of the drives of the coordinate table, deflection of the electron beam 2.

This machine controls the electron beam installation in

parts of the software move the electron beam along the substrate (in this case, both stepwise and scanning modes are performed along the rows of the microraster) and the coordinate table, the substrate of which is installed, as well as the formation of technological processing modes in order to manufacture photo masks or directly compositing integrated circuits.

The preparation of control information for the machine consists in dividing the topology of the photomask into basic geometric figures reproduced by the machine and presenting the information describing these figures in the language of the machine. The preparation of information in this form at the stage of studying electronic technological methods created certain conveniences for the operator-technologist, since fairly simple technological tasks were programmed, and the main attention was paid to ensuring maximum simplicity of the operator's communication with the machine in the study of electron-beam processes. The preparation of control, information at the level of basic figures for reproducing complex geometric patterns, such as topological structures of large integrated circuits containing several thousand angular points of contours, is a laborious process. The need to use expensive universal computing machines makes it difficult to quickly manufacture photo masks and increases the cost of microchips. In addition, an increase in the amount of input information leads to a lengthening of the program carrier (for example, punched tapes) and, as a rule, to a decrease in the reliability of the control system, for storing the same information a considerable amount of machine memory is required. There is no possibility to operate with information presented in a collapsed form, for example, with an array of topology data in the form of coordinates of break points (corner points) of contours. The aim of the invention is to increase the work efficiency by reducing the laboriousness of the process of preparing the program and reducing the amount of memory for storing data. To do this, a block for determining the angular coordinates of topological fragments is inserted into the machine, connected by corresponding inputs and outputs to the control unit and to the code bus, and a block for determining the coordinates of anchor points and the type of basic shapes connected by inputs to the output of the block for determining the angular coordinates of topological structure fragments and code bus, and outputs connected to the corresponding input of the control unit and to the code bus. FIG. 1 shows a structural diagram of the machine; in fig. 2 - a fragment of the t-opological structure; in fig. 3 and 4 are diagrams explaining the implementation of splitting and selection of elementary figures. The machine contains a blocker transmitter for entering programs from punched tapes; loan device 2 for storing a program; the control unit 3, which distributes information and interacts with the machine units; a buffer memory 4 for storing current information; computing unit 5, which performs the functions of controlling the electron-beam installation in terms of forming technological processing modes, calculating increments of the coordinates of the points of the trajectory with making necessary geometric transformations (rotating images, transferring the origin, mirroring, changing the scale), controlling the drives of the coordinate table, and also assigning the location of the beam to marker marks in order to compensate for the angular error or the error of the installation of the origin inat and image scale; block 6 of communication with the control object, and transforming the digital values of the control quantities into proportional control actions; block 7 for determining the angular coordinates of the topological structure fragments; and block 8 for determining the coordinates of anchor points and the type of basic figures. Nos. 9–20 denote links. Block 3 has two-way communications for exchanging control information with the transmitter unit 1 and the storage device 2, as well as with the computing unit 5 through the buses 17 and block 7 through the buses 18. When accessing the buffer storage device, the unit 3 generates signals on the bus 16. On bus 19, block 3 receives signals in the process of converting the topological structure, under the influence of which the blockZ distributes information to the memory of the machine. Tires 9-13 are intended for the transfer of regulatory influences: a deflection system of an electron-beam installation is connected to the tire 9; a blanking signal bus 10 — for modulating a beam current; tires 11 and 12 control the magnitude of the beam current and accelerating voltage; bus 13 control drives the coordinate table. Tires 14 and 15 to block 6 receive signals from sensors of the true position of the coordinate table and marker signs, respectively. The exchange of numerical information between the blocks of the machine is carried out on the code bus. The machine operation program is entered from the punched tape into the memory 2. The initial data is a description of the topological structure, represented by the coordinates of the corner points of the contour. If the figure contains internal contours, forming windows in it, for example, AiBiBiFiAi and A2B2V2G2A2 contours (see Fig. 2), then its description indicates the corresponding feature, and descriptions of these contours are presented separately. In addition, when describing the figure, points are formed that form depressions in the contour in the direction of decreasing ordinates (for the case under consideration, point 3 in Fig. 2). Before carrying out the process of electron-exposure exposures, the figure and fragments are divided and the basic figures are extracted from them, which are carried out by the joint operation of blocks 7 and 8. The essence of the division lies in the cross-section of the figure bounded by the contour, straight

mi passing through the corner points of the contour parallel to one of the orthogonal axes. In the following, we will consider the cross section of the figure of a straight, parallel axis of the abscissa.

An example of such a partitioning is shown in FIG. 2 and is illustrated in FIG. 3 and 4. To carry out these transformations from memory 2 to buffer memory 4, the signals generated by block 3 are entered into coordinates of special points, such as contour trough points and vertical contour points having minimum values of ordinates. In addition, in block 7, under the influence of signals on the bar 18i, the coordinates of the reference point, as which the contour point is automatically selected, having the minimum values of the ordinates of the UMIN, are added. If there are several such points, then one is chosen that also has the minimum abscissa value, for example, point A (see Fig. 2).

Next, from block 2 to block 7, the coordinates of points adjacent to the reference point are brought in, and as a result of pairwise comparison of the coordinates of interconnected points, the coordinates of the contour breaks in which the section of the figure is drawn are determined.

Thus, in the case under consideration, it is determined that the AF is the base of the quadrilateral, since the UV value is equal to the value of Od and there are no other points on the AF segment. Since UV is less than Um and, moreover, UT is less than OV, then it should be cross-sectioned through point T. The missing corner point T of an AFTT quadrilateral is determined by assigning to it the ordinate of the point T and the abscissa of point A, since XA is equal to CB, i.e. the AB line is parallel to the ordinate axis. In general, the abscissa of the missing point is determined from the expression:

Wu, () (UT-UA)

X- ,, A + ---.

Thus, a quadrilateral is cut off from the figure, the coordinates of the corner points of which are transmitted to the block 8 by block signals under the influence of signals on the bus 20. In addition, the coordinates of the point T are entered into the memory 2 in the contour description, and the coordinates of points A and F from the description are removed, i.e., further operations are performed on the figure without the clipping portion. After that, in block 7, the values of the coordinates of the new reference point with the UMPD, for example, the point P, are entered, and the next figure is cut off in the same way.

Since when removing the cut points from the description of coordinates, the coherence of the remaining points may be disturbed, to eliminate this, the coordinates of the isolated points that are formed move within the information field of the memory, taking up the free space. Thus, in the case under consideration, instead of point A, the description of the newly formed point T is placed, point F is the last in the description of the array, and its removal does not violate the connectivity condition, and descriptions of points C and T are moved one position each to fill a vacancy in place of point P (position I and P in Fig. 3).

Similarly, the points of the inner contours that fall into the section field are included in the description of the outer contour. This process is illustrated by the positions 1P and IV in the diagram of FIG. 3. Due to the fact that the coordinates of the singular points that can affect the process of splitting the figure, are in

the buffer storage device 4 eliminates the waste of time associated with the analysis at each step of dividing all points of the contour to reveal specific ones.

The process of splitting a figure into fragments is completed when, in the description of the original one-connected contour or several unrelated contours, formed as a result of the section of the figure at special points

(positions CP-XV and FIG. 4), no more than two associated points remain. Thus, in the case under consideration, in the description of the figure, the points E and Z remain as a result of breaking the contour of the RTD and the points K and L belonging to the contour ZIKLMZ. The signal about the end of the splitting on the ISo bus goes to block 3 for indication to the operator.

Further transformation of the received fragments taking into account restrictions on the size

the deviation field and the set of basic figures is carried out by block 8. By successively searching the figures and comparing the coordinates of their angles with the coordinates of the bounding lines, the initial figure is divided into fragments,

which can be placed within a single deflection field. Since in each deviation field the coordinates are counted from their zero value, all angular points of the figures, outside the first deviation field, draw new values of coordinates, taking into account their initial value and deviation number, in which one or another figure is placed.

Next, an analysis of the figures within each deviation field is conducted, as a result of which figures are determined that are not included in the number of basic ones reproduced by one command. For example, the RSP triangle (see

FIG. 2) is neither isosceles nor RECTANGULAR and THEREFORE, it is divided into two right triangles, which are already basic figures. Similar operations are performed by the idiom.

and non-rectangular trapezoid. The coordinates of the reference points of the basic figures along the code line are influenced by signals on bus 19 into memory 2. At the same time, a sign is formed

Ida shapes (triangle, trapezoid, etc.),

which is the command to perform the procedure for building it. After writing to the block 2 commands to reproduce all the figures within one deviation field, a command is generated to move the coordinate table by an amount equal to the size of the deviation field, after which similar operations are performed on the figures of the next deviation field. As a result of this, in the storage device 2, the program for playing back the pattern on the photomask blank is accumulated. In accordance with this program, block 5 performs the construction of the figures in a predetermined sequence, controlling the movement of the electron beam of the n coordinate table by acting on the electron beam installation of control signals generated by block 6 on buses 9-13. Control information is exchanged between blocks 5 and 3 on buses 17i and ITg.

Since all the information needed to reproduce this figure is 13 buffer storage device 4, n during its construction does not access the storage device 2, the processing of the substrate and the preparation of the program for the next field deviation are combined in time, which is useful in terms of improved performance.

The process of preparing the work program is completed when the last base figure is transferred to memory 2. At the same time, a corresponding signal is formed on the pin 9, and in block 3 the final address of the program stored in memory 2 is fixed. When the substrate reaches this address, a program end signal is generated on bus 172, which blocks all control channels of the electron beam installation; at the same time, unit 3 starts transmitter 1 to enter the next information or, if it is not ready, it stops the machine, informing the operator.

Introduction of blocks of determining the angular coordinates of the topological structure fragments, determining the coordinates of anchor points and the type of basic figures into the masks allows you to operate with an input language of a higher level, which leads to a reduction in the complexity of the work program preparation process, and, consequently, to increase machine efficiency .

The above can be illustrated by the following example. For preparation

the topological drawing program shown in FIG. 2, for a known machine, it is necessary to analyze the size and position in space of 16 basic figures, which in the most optimal case can be satisfied by specifying at least 50 points, while in the considered machine this description is limited to specifying 27 points. If we take into account the fact that unequal trapeziums and triangles increase the number of basic shapes for a known machine, then it can be argued that this difference in the number of specified points increases even more.

The implementation of the inserted blocks can be accomplished with the help of integrated microprocessors, while developing the appropriate software created on the basis of a one-way memory machine and

0 firmware.

Claims (2)

Invention Formula Digital machine for controlling electron beam microprocessing processes, containing a transmitter unit, a storage device, a control unit, a buffer storage device, a computation unit connected to the code bus and control signal buses, a communication unit with an addr, input and output which are connected respectively to the output and input of the computing unit, the input and output of the machine are connected to the corresponding input and output of the communication unit with the object of direction, 5 which, in order to increase the effect work by reducing the complexity of the process of preparing the program and reducing the amount of memory for storing data, the block for determining the angular coordinates of the topological structure fragments, which are connected by corresponding inputs and outputs to the control unit and to the code chip, and the block for determining the coordinates of anchor points and A view of the basic 45 figures connected by inputs to the output of the block for determining the angular coordinates of the fragments of the topological structure and the code bus, and the outputs connected to the corresponding input of the block control and to the code bus. Sources of information taken into account in the examination 1. USSR author's certificate №477417 Cl. G 06F 15/20, 1974. 55 2. For the number № 2074514/24, cl. G 06F 15/20, 1974, by which the decision to issue an author's certificate was made. YYYYYY.G P, 772 20 y TO 9 /, / ttt П J8 9 2 8, IPUi.l