JPS627718B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a plurality of infrared detection elements.

In general, manufacturing an infrared sensing device involves forming an infrared sensing element, disposing such element on a suitable substrate, providing electrical connections to the element,
It consists of testing the component provided with such connections and finally encapsulating the component and contacts in a suitable envelope. Some infrared detection devices are composed of individual infrared detector elements, while others are composed of a plurality of infrared detection elements arranged, for example, in a linear array. The operation of these devices is based on the intrinsic photoconductivity of infrared-sensitive materials.
- In the case of manufacturing elements of devices that are affected by . For example, cadmium mercury telluride (cadmium mercury telluride)
In the case of an infrared detection device using an infrared sensitive material such as telluride, it is difficult and expensive to prepare. Therefore, manufacturing processes that allow the economical use of such materials are important. However, there are problems with the different sizes and characteristics of the elements and the wide variation in requirements for the mounting structure depending on the particular infrared detection device to be manufactured, e.g.
area) as small as 25 microns x 25 microns or as large as 2 mm x 2 mm. It is uneconomical to have to use a new slice of expensive infrared-sensitive material for any different shape of the sensing element. Furthermore, if an array of multiple detection elements is formed on a single common body of infrared-sensitive material, if only one element is found to be defective upon testing, the array of elements may be This results in a waste of material as the entire single substrate consisting of 300 .ANG. has to be discarded. Another problem with monolithic technology is the spacing between individual elements, particularly in groups of elements formed on a single substrate. When isolation of the active surface area of such a device formed on a single substrate is created by an erosion process,
Generally, when etching a body of infrared sensitive material, the width of the channel is usually significantly wider than the thickness of the body of material, thereby placing a limit on the minimum possible separation that can be achieved. Even if the thickness of the material body is reduced to 6 microns, the separation of the individual elements will still occur due to corrosion.
It is not easy to reduce the thickness to 12 microns or less. Furthermore, if the individual elements are formed separately before being reduced to the final element thickness, handling and processing of such a thin body of material is extremely difficult.

Another problem that arises in individual element systems and array element systems is providing electrical connections to the infrared sensing elements. Traditionally, this has been accomplished by joining conductive wires leading to the metallized surface portions of the components, for example by thermocompression or soldering. For example, nailhead connections (nailhead
The deformation of the conductor tip associated with the bonding operation, as occurs in bonding, causes the area of the surface portion of the element to which the conductors are bonded to be sufficiently adapted to the final deformed conductor tip such that the deformed conductor tip lies completely on the element. A process must be carried out to make this happen. Such a process not only significantly complicates device design, but also limits achieving the minimum possible separation between adjacent devices in the device array. Problems also arise when the other end of the conductor is connected to the lead-out conductor, for example by soldering.

Other problems associated with the so-called monolithic technology orientation to device manufacturing arise, for example, when manufacturing multi-element detection devices in which the separation of the devices in a linear array is not uniform. Differences in spacing between sensing elements may be desirable in some cases. For example, in some applications it may be desirable to have different resolutions at different locations in the array of sensing elements. In these cases, the detection elements must be spaced closer together in areas where the resolution is to be increased than in areas where the resolution is to be reduced. Forming multiple elements on a single substrate with different spacings between the elements in different parts of the element array is extremely difficult and extremely expensive in terms of the materials required.

The present invention comprises a body of infrared sensitive material having a generally rectangular surface structure, and a plurality of on opposite sides of the photosensitive area of the element a pair of separately spaced low resistance electrical contacts on the surface of the body. A method of manufacturing an infrared sensing element comprising: 1) depositing a wafer of infrared sensitive material on a support; and 2) forming a plurality of substantially parallel first channels dividing the wafer material into a plurality of substantially parallel strip sections. form,
3) the thickness of the strip portion is then reduced by curving the longitudinal edges of the strip portion; and 4) a plurality of generally parallel extending second channels are formed in the wafer of the strip portion. forming in the material substantially perpendicular to the length of the strip portion to define on the support an array of generally rectangular shaped basic body portions of infrared sensitive material having curved edges on two opposite sides; and 5) depositing a conductive material to form a pair of separately spaced apart and adjacent contact layers on oppositely located curved edges on the surface of each base body portion.

The method of the present invention described above has advantages such as material savings, easy provision of elements with different photosensitive areas, high detection performance, small separation between elements in multi-element devices, and external electrical connections as described below. It has the advantage of being easy to install. The method of the present invention provides the elements as individual elements rather than as monolithic assemblies, which facilitates assembly and contacting in the desired manner during these later steps in the manufacture of infrared sensing devices. In particular, providing a device with contact layers adjacent to oppositely located curved edges allows the electrical connection provided by the deposited conductive layer to facilitate subsequent processing of the device in an individual or multi-element device. Allows for assembly. This is because it is no longer necessary to connect the wires by soldering, which has the drawbacks mentioned above. Assembly of individual elements on the substrate is
This can be achieved, for example, by coating the element on an insulating substrate with epoxy resin. This method can be used for both single-element and multi-element devices. In multi-element devices, it is extremely advantageous that the spacing between the elements can be obtained as desired. The spacing between elements can be much smaller than in monolithically formed multi-element devices, and furthermore, for example in a linear array, the spacing between elements can be varied as desired. Furthermore, if necessary, a secondary array (two-
dimensional arrays) can be formed very easily.

The method of the present invention for forming a device may include any one of the following:
Significant savings in material can be achieved because, in a single wafer, elements of different photosensitive areas can be easily provided, for example by suitably choosing the separation of the plurality of second channels.
Furthermore, high device performance can be achieved because various surface treatments can be easily applied to the method of the present invention.

Before the wafer of infrared sensitive material is attached to the support, the wafer can be oxidized to form an oxide on the surface of the wafer to be attached to the support. In this case, the surface of the sequentially formed infrared sensitive element, which is located opposite the surface on which radiation is incident during operation, is provided with a layer that enhances the performance of the detection element.

After attaching a wafer of infrared-sensitive material to a support and before forming a complex first chain in the wafer material, the wafer is subjected to a thickness reduction treatment to reduce its initial thickness to remove such wafer from the support. material can be removed from the surface of the A multi-stage polishing process can be used for this thickness reduction process, e.g. by varying the size of the abrasive particles used in successive polishing stages of the process, or by varying the size of the abrasive particles used in the process until the desired thickness is achieved. This can be achieved by progressively reducing the damage caused to the crystal structure by moderately varying the hardness of the base lap.

The process of reducing the thickness of the strip portion and creating curvature of the exposed longitudinal edges of the strip portion is performed in combination with a polishing process followed by an etching process.

After forming the plurality of second channels in the wafer material, the exposed surface portions of the primary body portion are subjected to a passivating treatment. Passivating at this step of the process (e.g., after forming the array of substantially rectangular shaped elementary body portions) is advantageous because it allows the exposed sides of the elementary body portions to be passivated, and such exposure The side surfaces are adjacent to the main photosensitive area surface portions of the final formed element. This is desirable since devices formed without passive sides suffer from decreased performance when the device is exposed to high temperatures. A preferred method is to etch the exposed surface portions of the basic body immediately prior to passivation.

In a preferred example, the passivation treatment may be limited to a central surface area extending across the basic body portion parallel to the curved edge. In this passivation process, first a masking layer portion of, for example, a photoresist is deposited on the portion not to be subjected to the passivation treatment.
As a result, a passive layer is formed in the central surface area.

Next, the masking layer portion is removed. A new protective masking layer section, for example of photoresist, is then applied to the passivation layer section. In this case, portions of the protective masking layer are not applied to mutually opposed exposed strip portions of the passivation layer parallel to the curved edges. This exposed strip portion is then subjected to a material removal treatment, for example by a polishing process, in order to remove the passivation layer thereon. As a result, the passivation layer remains underneath the portions of the protective masking layer.

An electrically conductive contact material is then deposited over the entire surface of the substrate body portion and the protective masking layer portion, and the protective masking layer portion and the conductive material deposited thereon are then chemically removed. In this case, the deposited conductive material is removed from the active surface area of the device by a so-called "lift-off" technique. The use of this lift-off technique
In particular, when the deposited conductive material is gold, it is advantageous compared to first depositing the conductive material on the entire surface and then forming it by photolithographic techniques. This is because with photolithographic techniques it is not possible to attack the electrically conductive material without removing the material of the lower passive layer and possibly of the basic body part.

After applying the contact layer, the basic body is removed from the support by mechanical means, for example with a fine tool.
It can be removed by lifting with a tool.

When using mechanical means for removing the elementary body part, the elementary body part can be removed from selected positions of the array and the properties of the elementary body part and these characteristic parts in the array can be evaluated, e.g. by resistance, response, etc. Test procedures can be implemented to measure the sensitivity, cutoff wavelength, time constant, and detectivity D. In this case, a map plotting the properties of the basic body parts can be obtained, after which the basic body parts can be selectively removed to the desired properties of the detection device to be manufactured. Such testing means can be advantageously used when the properties of the initial starting wafer are not constant throughout the wafer.

To produce a multi-element infrared detection device, select a group of adjacently located basic body parts arranged on a support according to the evaluation characteristics of the basic body parts removed for testing purposes. It can be removed at will.

At least a plurality of generally parallel extending first channels can be formed in the wafer at uniform intervals. In this case, all basic body parts formed have the same cross-sectional dimensions between the curved edges of the two opposite sides. By varying the spacing of the plurality of second channels formed in a predetermined strip of infrared-sensitive material, the width of the basic body portion, i.e., the cross-section in the direction parallel to the curved edges of the two opposite sides, can be varied. Dimensions can be varied. In this way, multiple basic body portions of at least two different sizes of active surface area can be formed on any one starting wafer.

The method of the invention can be used for the production of infrared detection elements of various materials, especially high cost materials. One such material is cadmium mercury telluride, but since it takes a long time to manufacture the material with the desired properties, it is desirable to be as economical as possible in device formation. Despite this, the method of the invention can also be advantageously applied to other materials which have no bearing on material cost savings in the production of infrared detection elements, such as indium antimonide.

The invention will now be described with reference to the accompanying drawings.

The accompanying drawings are not shown to scale. In particular, the thicknesses of the various layers relative to the extending lateral spacing are smaller than shown in the drawings.

As a specific example, the production of a large number of cadmium mercury telluride infrared detection elements in the range of 2000 is described. The amount of cadmium mercury telluride used is approx.
Has a cutoff wavelength of 12 microns.

As starting material a diameter of approximately 10 mm and a diameter of approximately 0.5 mm
A disk-shaped wafer of thick cadmium mercury telluride was used.

A wafer 1 is fixed onto a ceramic polishing block 2 using a wax layer 3. The polishing prong has a protruding shoulder with a height of 200 microns. The surface of the wafer protruding from the shoulder is polished using a rotating machine using a base lap and an abrasive slurry. Polishing is done in a multi-stage polishing process. In this case, each polishing step progressively reduces the flaws caused in the crystal structure in the previous polishing step. This step-polishing process results in a final wafer thickness of 200 microns. This progressive scratch reduction process can be accomplished using sequentially finer abrasive particles and baselap. This polishing continues until the surface of the wafer is level with the surface of the shoulder of the polishing block 2. In order to remove the remaining surface scratches, a corrosion treatment is performed using a corrosive agent containing bromine dissolved in methanol.

A passivation treatment is then applied to the wafer 1 which is still attached to the polishing block 2. This applies this treatment to the exposed top and side surfaces.

FIG. 1 shows a 200 micron thick wafer 1 with an oxide surface layer 4. FIG.

The wafer 1 is removed from the polishing block 2 and deposited via the oxidized major surface onto another polishing block 5 of high density alumina. The support formed by the polishing block 5 has a shoulder of 25 microns in height;
A tantalum layer 6 is deposited on the inside of the shoulder and on its surface. The wafer 1 is attached to the tantalum layer 6 with a wax layer 7.

Although the preformed oxide surface layer 4 is shown in FIG. 2, this oxide surface layer 4 is omitted from FIGS. 3 to 19 for convenience of explanation. The stepwise polishing process is carried out using a rotary lapping machine with an alumina slurry, and the particle size and base lap are selected such that the resulting flaws are progressively reduced in successive polishing stages. This polishing is carried out until the polished surface of the wafer 1 is approximately flush with the protruding shoulder of the polishing block 5. FIG. 3 shows the wafer 1 after this thickness reduction step, which wafer 1 has a thickness of about 25 microns.

A layer of photoresist is applied to the top surface of the reduced thickness wafer 1 adhering to the tantalum layer 6 on the polishing block 5 via a wax layer 7. A photomasking and developing process is then performed to form a large number of generally parallel strip-like openings in the photoresist layer. The wafer is then subjected to an etching treatment using a suitable caustic agent for cadmium mercury telluride to form a plurality of substantially parallel first channels 8 in the wafer, and the cadmium mercury telluride is deposited on the polishing block to form a plurality of substantially parallel first channels 8. A plurality of strip portions 9 are formed. 4th to 5th
The figure shows a channel 8 and a strip 9. In this example, channel 8 has a width of approximately 50 microns and the total strip has a width of approximately 200 microns.

In the next step of the process, the portion of the photoresist layer remaining on the strip portion 9 is removed.
Thereafter, a thickness reduction process is performed to reduce the thickness of the strip section 9 to about 8 microns, while at the same time making the longitudinally extending upper edge of the strip section 9 curved. This process is carried out by a first polishing using a lapping machine using a fine grade pad and fine abrasive to reduce the residual thickness of the strip section 9 to approximately 12 microns, after which the strip section 9 is removed by etching. Remove approximately 4-5 microns in thickness of the section.

This corrosion causes the upper longitudinal edge of the strip to be rounded. By rounding the upper edge in this way, the gold contact layer 2
1 and 22 to make it easier to adhere (see FIG. 17). Furthermore, it was confirmed that corrosion has a sensitizing effect that provides high detection performance.
FIG. 6 shows a cross section of the strip section 9 after the corrosion treatment. Although this figure does not show the rounded curvature of the longitudinal edges, in reality the curvature should be at least 15mm from the base at each longitudinal edge.
The cross section extends over a distance of microns. Also,
During the polishing process, which reduces the thickness from 12 microns to 7-8 microns, the exposed wax layer portions in channel 8 are removed. As shown in Figure 6,
Wax layer 7 is present only on the underside of each strip section 9.

The next step in the process is to deposit a layer of photoresist on top of the strip portion. removing from the photoresist layer a plurality of substantially parallel extending strips located perpendicular to the strip portion 9 using a conventional photomasking process;
The exposed material of the strip section 9 is etched using a suitable caustic agent for cadmium mercury telluride to form a plurality of generally parallel extending channels 10 in the wafer material of the strip section, and the exposed material of the cadmium mercury telluride is etched onto the polishing block. forming an array of substantially rectangular basic body portions 11 . FIG. 7 shows a plan view of a portion of the wafer after the channel 10 has been formed and the remaining portions of the photoresist layer used for masking in the formation of the basic body portion 11 have been removed. FIGS. 8 and 9 show cross sections taken along lines - and - in FIG. 7, respectively. Figure 8 shows the basic body part 1 of the two opposite sides.
1 shows a rounded curved edge, whereas the other two sides of the basic body part have substantially vertical edges (FIG. 9). In this example, the width of the channel 10 upon final corrosion is approximately 30 microns, and the final surface area of the basic body portion 11 is approximately 200 microns x 200 microns, as shown in FIG.
Make it 50 microns.

In the next step of the process a photoresist layer 1 is applied to the exposed surface parts of the surface wax layer 7 of the basic body part 11 and to the tantalum layer 6 on the polishing block 5.
2. A photoresist layer 12 is formed by a photomasking-development process, thereby forming an opening 13 (FIG. 10). This opening extends parallel to the channel 8 and is approximately 50 microns exposed at one end of the basic body portion 11 where there is a rounded curved edge and exposes an adjacent portion of the tantalum layer 6 on the polishing block 5. , from which portions of the wax layer 7 have been previously removed in a thickness reduction polishing step. FIG. 10 shows a cross-sectional view corresponding to the cross-section of FIG. 8 showing the photoresist layer 12 and the opening 13. As shown in FIG.

A 0.5 micron thick layer of gold is then applied by sputtering. Gold is photoresist layer 1
2 and in the opening 13. The photoresist layer 12 is then dissolved in a suitable solvent and the gold deposited thereon is removed by a lift-off technique.
FIG. 11 shows about the area forming the contact between the upper surface of the basic body part 11 and the tantalum layer 6 on the polishing block 5.
10 shows a cross-sectional view corresponding to that of FIG. 10 with a gold layer strip 14 50 microns wide. Gold layer portion 14 is necessary to make electrical connections to tantalum layer 6. This is because, in the absence of the gold layer portion 14, the basic body portion 11 would have an oxide surface layer 4 on its underside, and the basic body portion 11 would have changed from the tantalum layer 6 to the wax layer 7.
This is because the basic body portion 11 is actually completely electrically isolated.

Another layer of photoresist 15 is applied to the top side of the assembly thus formed, and rectangular strip-shaped holes 16 about 80 microns wide are formed in photoresist layer 15 by a photomasking-development process. . FIG. 12 corresponds to the cross-sectional view of FIG. 11 and shows a strip-shaped hole 16.
is located centrally on the surface of the basic body portion 11.
These strip-shaped holes 16 exhibit a width in the direction of the major lateral dimension of the basic body portion, ie, in the direction of the cross-section of FIG. 11, and are slightly larger than the desired final dimension of the active surface area of the basic body portion.

In the presence of the formed photoresist layer 15, the exposed surface portions are anodically etched to remove material to a thickness of less than 1 micron. This anodic etching process is performed using the tantalum layer 6, which connects the gold layer portion 14 as an anode to the exposed surface portion of the device. Next, a passivation treatment is applied here. FIG. 12 shows the passivation layer 17 formed on the exposed surface of the basic body portion 11 in broken lines.

The remaining portions of photoresist layer 15 are then dissolved. 13-14 show a plan and cross-sectional view of an assembly having a gold layer strip 14 thus formed, with a passivation layer 17 on the surface portion. For convenience of explanation, the gold layer strip 14 is
In the plan view of FIG. 3, it is shown with diagonal lines.
As the photoresist layer is removed from the portion of the channel 10 between the basic body parts 11 along the strip holes 16, the longitudinal side portions of the basic body parts 11 are passivated. This processing can advantageously be accomplished at this stage, ie after device formation.

The next step is to deposit a photoresist layer 18, which is then subjected to a photomasking-development process to form holes. The passive surface area on each base body portion 11 is coated with a photoresist layer 18 except for the opposing peripheral strip portions 19 extending generally parallel to the curved edges of the base body portion 11 to form the apertures. and leave it behind. Additionally, the photoresist layer 18 remains in the channel 10 between the base body portions and in the channel 8 shown in FIG. It partially overlaps the contact strip portion 14.

A material removal process is then carried out on the exposed strip portions 19 of the passive surface areas where the formed photoresist layer 18 is present. This is done by a polishing process using a wrapping cloth and a fine abrasive. In this case material removal can be carried out effectively. This is because photoresist layers generally have greater polishing resistance than passive surface layers and are significantly thicker. In this case, the passive surface layer is removed from the exposed strip portion 19.

After this polishing process, a 0.5 micron thick gold layer 20
is deposited on the top surface of the assembly including the photoresist layer portion 18 and the exposed surface portions of the basic body portion 11. Gold is deposited by sputtering. FIG. 16 corresponds to the cross-sectional view of FIG. 15, but shows the surface of the photoresist layer portion 18 and the basic body portion 1.
The exposed surface portion of 1 is coated with a gold layer 20. The gold layer 20 has been removed by the polishing process to remove the passive surface layer along the exposed strip portion 19 (FIG. 15) of the passive surface area.
contacts the surface of the basic body part 11 where no such passive layer portion is present, ie the edge of the gold layer contact 20 aligns with the edge of the remaining portion of the passive surface layer.

Following the deposition of the gold layer 20, the photoresist layer 1
The remaining portion of 8 is dissolved and the overlying portion of the gold layer is then removed by a lift-off action. A pair of gold contact layers 21 and 22 are thereby formed via an active surface area of 50 microns by 50 microns.
remains on each basic body portion 11. Contact layer 21
extends over the curved edge on one side of the element, and the contact layer 22 extends over a portion of the remaining portion of the gold strip 14 covering the curved edge on the other side of the element. The contact layer 22 is partially thicker than the contact layer 21 on the other side and is therefore asymmetrical.

Figures 17-18 show the assembly in cross-section and in plan view, respectively, after dissolving photoresist layer portion 18. The contact layers 21 and 22 thus formed on the pre-curved edges of opposite edges of the basic body part are provided with external electrical connections to the basic body part by depositing a conductive material on these curved edges. A connecting layer to be used in the manufacture of an infrared detection device can be provided by forming the connecting layer.

In the process steps shown in FIGS. 17-18, there are numerous areas of approximately 2000 cadmium mercury telluride element body portions 11 with contact layers attached to polishing block 5 through wax layer 7. It shows. Depending on the processing means, ie, starting from slices cut from an ingot, there is some variation in the properties of the basic body part 11 over the entire array. In order to be able to use the basic body parts 11 effectively without producing significant defects, the next step in the process is to separate the individual basic body parts 1 from selected positions of the array.
1 is removed and the element thus removed is subjected to known test procedures as described above. In this measure,
The characteristics of the sensing elements over the entire array can be measured and plotted on a map. This map can then be used in the manufacture of an infrared detection device to selectively remove one or more basic body parts 11 as required. In practice, in the manufacture of multi-element devices, a group of adjacent elementary body parts of an array on a polishing book is used to evaluate the characteristics of the individual elementary body parts, which have been previously removed for testing purposes. Therefore, it can be selectively removed.

In this example, the basic body part 11 is mechanically removed from the polishing block separately by lifting from the wax layer with a sophisticated tool.

FIG. 19 shows an enlarged plan view of one basic body part 11 attached to the polishing block 5 through the wax layer 7, and FIGS. A cross section is shown. In Figures 20 and 21,
The passivation layer formed before fixing the wafer on the polishing block 5 is indicated by a dashed line 4. The passivation layer formed after the etching treatment of the active surface layer after device formation is indicated by a dashed line 17. Also, as is clear from FIG. 21, this extremely thin surface layer is formed along adjacent portions of the longitudinal sides of the basic body portion 11. The lateral boundaries of the region of the top surface which has been subjected to passivation treatment are indicated in FIG. 19 by dashed lines 24.

It can be seen from FIG. 20 that a 0.5 micron thick gold contact layer extends over the curved edge on one side of the basic body portion 11. On the opposite curved edge of the basic body portion 11 there is a residual portion of a gold strip 14 0.5 microns thick. This gold strip 1
4 has a 0.5 micron thick gold contact layer 22.
is present, and this contact layer 22 further extends into contact with the upper surface of the basic body part 11. To this end, on one side of the basic body part the composite gold contact layer 14, 22 has a thickness of 1 micron, whereas on the other side the gold contact layer has a substantially uniform thickness of 0.5 micron.

The present invention can be modified in various ways within the scope of the present invention. For example, it can be applied to the manufacture of infrared detection elements of other materials such as indium antimonide. Instead of the arrangement shown in FIG. 17 in which all elementary body portions 11 are formed of the same size with equal active surface areas, at least two differently sized elementary body portions 11 are formed from a single starting wafer. It can be used to provide an array consisting of. This can easily be done in the first photomasking step when forming the width of the strip portion 9. Although in the embodiment described above it consists of providing an ohmic contact layer on the basic body part with a homogeneous material composition, the operation of which in the use of the detector is due to its inherent photoconductivity, it is also within the scope of the invention. forms a p-n junction in the photosensitive area of the basic body part, and connects the contact layer contacting the p- and n-type regions, respectively, in the basic body part to the curvature on two opposite sides of the photosensitive area of the basic body part. It can be made to extend over the edge.

In implementing the present invention, the following terms can be set as conditions for implementation.

1. Before attaching a wafer of an infrared-sensitive material to a support, the wafer is oxidized to form an oxidized surface on at least the surface of the wafer to be attached to the support.

2. After attaching the wafer of infrared-sensitive material to the support and before forming the plurality of first channels in the wafer material, subjecting the wafer to an initial thickness reduction treatment through the surface of such wafer remote from the support. .

3. The process of reducing the thickness of the strip section and curving the exposed longitudinal edges of such strip section consists of a combination of etching and polishing processes.

4. Passivating the exposed surface portions of the primary body portion after forming the plurality of second channels in the wafer material.

5 Corrosion treatment is applied to the exposed surface of the basic body immediately before passivation treatment.

6. Confining the passivation treatment to the central surface of the basic body part, extending this area across such basic body part, and having such area on opposite sides of such area adjacent to the curved edge of the basic body part. be limited by the masking layer.

7 After passivation and before applying the contact layer:
said masking layer portions are removed, and another masking layer is deposited and defined, with the exception of opposing peripheral strip portions extending each passive surface area approximately parallel to the curved edges of the basic body portion; A material removal process is carried out on the exposed strip portions of the passive surface area where such masking layer portions are present.

8. The material removal process is performed by a polishing process.

9 said further masking layer comprises a photoresist, an electrical contact layer is formed by depositing a conductive material on the exposed surface portions of the basic body portion and the photoresist masking layer, and then depositing a conductive material on the photoresist masking layer and the conductive material deposited thereon. Formed by chemical removal.

10 After application of the contact layer, the basic body part is removed from the support separately by mechanical means.

11 Remove the basic main body part from the selected part of the array,
Testing procedures are provided to evaluate the properties of the basic body portion and the distribution of such properties in the arrangement.

12 To produce a multi-element infrared detection device, a group of adjacently located basic body parts of the array on the support are selectively selected according to the evaluation characteristics of the removed basic body parts for test procedures. Remove it.

13 forming at least a plurality of substantially parallel extending first channels in the wafer with substantially uniform spacing;

14 The infrared-sensitive material is cadmium mercury telluride.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a cadmium mercury telluride wafer placed on a polishing block in the manufacturing process after surface treatment, Figure 2 is a cross-sectional view of the wafer after being placed on another polishing block, and Figure 3 is a cross-sectional view of the wafer after being placed on another polishing block. A cross-sectional view of the wafer remaining on the polishing block after the thickness reduction treatment, FIG. 4 is a plan view of the wafer on the polishing block shown in FIG. 2, and FIG. 5 is a cross-section on the - line of FIG. 4. 6 is a cross-sectional view of the wafer on the polishing block after the thickness reduction treatment, FIG. 7 is a plan view of a portion of the wafer after another thickness reduction treatment, and FIGS. 10 to 12 are cross-sectional views of the wafer in the sequential processing steps, FIG. 13 is a plan view of the wafer in the processing steps after passivation treatment, and FIG. 14 is the 13- 15 and 16 are cross-sectional views of the wafer in successive further processing steps; FIG. 17 is a cross-sectional view taken along the line - of FIG. 18; and FIG. 18 is a sectional view of the individual basic bodies of the wafer. Top view of the wafer in the processing step after providing the contact layer on the part, first
FIG. 9 is an enlarged plan view of one basic body portion with contact layer deposited on the polishing block, and FIG.
21 are sectional views taken along lines - and - in FIG. 19, respectively. 1... Wafer, 2... Polishing block, 3,
7... Wax layer, 4... Oxide surface layer, 5...
Polishing block, 6... Tantalum layer, 8, 10...
1st channel, 9... Strip part, 11...
... basic body part, 12, 15, 18 ... photoresist layer, 13 ... opening, 14 ... gold layer strip, 16 ... strip-like hole, 17 ... passive layer, 19 ... passive surface area Exposed strip portion, 20... gold layer, 21, 22... gold contact layer.

Claims (1)

Claims: 1. Consisting of a body of infrared sensitive material having a generally rectangular surface structure, on the surface of which a pair of separately spaced low resistance electrical contacts are provided on opposite sides of the photosensitive area of the element. A method of manufacturing a plurality of infrared sensing elements comprising: 1 depositing a wafer of infrared sensitive material on a support; 2 forming a plurality of substantially parallel first channels dividing the wafer material into a plurality of substantially parallel strip sections; 3. The thickness of the strip portion is then reduced by curving the longitudinal edges of the strip portion; and 4. a plurality of parallel extending second channels are formed in the wafer of the strip portion. forming an array of generally rectangular-shaped basic body portions of infrared-sensitive material formed in a direction substantially perpendicular to the length of the strip portion of the material and having curved edges on two opposite sides on the support; 5. A plurality of infrared sensing elements, characterized in that a conductive material is then deposited to form a pair of separately spaced and adjacent contact layers on oppositely located curved edges on the surface of each elementary body portion. How to manufacture.