Detector and lidar system

Abstract

Detector (100) for a lidar system (200), comprising a series of adjacent radiation-sensitive pixels (110), wherein the pixels (110) of the row have such contours that opposite sides (163, 164, 165) of neighboring pixels (110) deviate at least partially from a perpendicular direction (151) to an extension direction (150) of the row, wherein adjacent pixels (110) of the series extend side by side in overlapping areas (155) along the extension direction of the series, and wherein the pixels (110) of the row have interlocking contours.

Description

[0001] The present invention relates to a detector for a lidar system and a lidar system.

[0002] This patent application claims priority from German patent application 10 2015 101 902.7, the disclosure of which is hereby incorporated by reference.

[0003] Driver assistance systems are increasingly being used in today's motor vehicles to increase vehicle safety. One example is a LIDAR (light detection and ranging) system for measuring the distance of objects. Such a system comprises an emitter for emitting pulsed infrared radiation, a detector for detecting the radiation, and an evaluation unit for signal processing. During operation of the system, the radiation pulses emitted by the emitter can be reflected by an obstacle in front of the vehicle and, after passing through an optical system connected upstream of the detector, can be detected by the detector. The distance between the obstacle and the vehicle can be determined from the time of flight of the radiation (time-of-flight measurement).

[0004] In a conventional design, the reflected radiation is detected using a pixelated photodiode detector (photodiode array). The detector has radiation-sensitive pixels with rectangular contours arranged side by side in a row. Radiation-insensitive intermediate regions are located between the pixels by design. This serves, among other things, to reduce crosstalk between the pixels. Radiation reflected from an obstacle and only reaching an intermediate region may therefore not be detected. This poses a major risk for the safety-relevant lidar system.

[0005] To avoid the problem described above, a modified optics system can be installed upstream of the detector, allowing the incident radiation to be directed onto the detector in a defocused manner or concentrated onto individual pixels. This is associated with disadvantages such as blurred images and increased costs.

[0006] EP 2 451 150 A2 describes a system for capturing a color image of an object. In addition, a distance measurement is performed to perform color correction and create a 3D image. The distance measurement is performed using a time-of-flight radiation source and a time-of-flight sensor. In one embodiment, the time-of-flight sensor has hexagonal pixels arranged in a honeycomb pattern.

[0007] WO 2006 / 001615 A1 describes a CMOS image sensor. In one embodiment, the sensor has diamond-shaped pixels.

[0008] US 2013 / 0 153 748 A1 describes a solid-state image sensor comprising pixel units with multiple pixels. The pixels have triangular or hexagonal shapes.

[0009] DE 10 2012 203 596 A1 describes a time-of-flight sensor with a light-shielding coating.

[0010] The object of the present invention is to provide an improved solution for a detector and for a lidar system.

[0011] This object is achieved by the features of the independent patent claims. Further advantageous embodiments of the invention are specified in the dependent claims.

[0012] According to one aspect of the invention, a detector for a LIDAR (light detection and ranging) system is proposed. The detector comprises a row of radiation-sensitive pixels arranged adjacent to one another. The pixels of the row have contours such that opposite sides of neighboring pixels extend at least partially deviating from a direction perpendicular to a direction of extension of the row.

[0013] The detector has a row arrangement of separate radiation-sensitive pixels for radiation detection. Between the pixels, the detector can be radiation-insensitive or have radiation-insensitive intermediate regions. The contours or geometric top view shapes of the pixels deviate from a rectangular shape. Here, the pixels are designed such that opposite sides of adjacent pixels each extend at least partially deviating from a perpendicular lateral direction to a direction of extension of the row, i.e., at least partially not perpendicular to the direction of extension of the pixel row. These features relate to a top view of the detector's pixels.

[0014] Such a geometrical design of the pixels offers the possibility of avoiding the presence of dead zones along the array's extension direction, where no radiation can be detected, despite the separate pixels or the radiation-insensitive intermediate regions separating the pixels. Thus, continuous radiation detection across all pixels in the array is possible along the extension direction.

[0015] This advantage can be achieved at no additional cost. Simply design the detector with the pixel geometry described above.

[0016] With regard to application in a vehicle's lidar system, the detector can be arranged such that the pixel row is oriented horizontally, and thus the extension direction of the row is parallel to the horizontal direction. With this orientation, the opposite sides of adjacent pixels can be at least partially non-perpendicular to the horizontal direction, and thus, continuous radiation detection can be provided with respect to the horizontal direction. In this way, not only extended objects but also critical small obstacles with a small horizontal and possibly large vertical extension can be reliably detected based on the radiation reflected from them and reaching the detector. Such obstacles include, for example, people, trees, pillars, columns, etc.

[0017] Further possible details and designs of the detector are described in more detail below.

[0018] The pixels can be located in the front area of ​​the detector. During operation of the associated lidar system, the detector can face the radiation to be detected.

[0019] The opposite sides of adjacent pixels can be corresponding to each other or at least partially parallel to each other.

[0020] The radiation-insensitive intermediate regions present between the pixels can have a linear or strip-shaped top view. Furthermore, the intermediate regions can, corresponding to the opposite sides of the adjacent pixels, extend at least partially deviating from a direction perpendicular to the direction of extension of the pixel row.

[0021] The pixels can have lateral dimensions in the range of several hundred microns or even other, for example, larger dimensions. The intermediate regions can have a width in the range of several tens of microns or even other, for example, smaller, widths.

[0022] In a further embodiment, the detector has a front shield. The shield has a plurality of openings assigned to the pixels. The contours of the pixels can be defined by the contours of the shield's openings. Furthermore, the radiation-insensitive intermediate regions between the pixels can be defined or formed by the shield. The shield can be made of a metallic material.

[0023] Different geometric gradients are conceivable for the opposite sides of adjacent pixels, viewed from above. In one possible embodiment, the opposite sides of adjacent pixels in the row extend in a stepped manner. For example, the sides can run perpendicular to the direction of extension of the row in some sections, and between such sections, for example, diagonally to it or in the direction of extension of the row.

[0024] In a further embodiment, the opposite sides of adjacent pixels in the row extend in a zigzag shape. In this case, the sides can have sections that extend obliquely to the direction perpendicular to the direction of extension, and thus also obliquely to the direction of extension of the row. With a zigzag shape, a configuration is possible in which all pixels in the row, including the two pixels at the two ends of the row arrangement, have substantially identical dimensions or surface dimensions.

[0025] With regard to the aforementioned and other possible geometric shapes of the pixels, it may also be considered that the pixels have at least partially curved contours. In this way, the occurrence of an increased electric field strength can be suppressed.

[0026] In a further embodiment, adjacent pixels of the row extend on opposite sides at least to locations that each have matching heights relative to the direction of extension of the row. The term "height" used here refers to a position relative to the direction of extension of the pixel row. The aforementioned embodiment can therefore also be described such that adjacent pixels of the row extend at least to matching positions relative to the direction of extension of the row.

[0027] If adjacent pixels of the row extend to locations that have identical heights relative to the direction of extension of the row, or in other words, if adjacent pixels extend to identical positions relative to the direction of extension of the row, radiation can be detected alternately across the pixels along the direction of extension of the pixel row. In this case, the opposite sides of the pixels separated from one another by the radiation-insensitive intermediate regions can each be partially located at the same positions or end at the same positions relative to the direction of extension of the row.

[0028] According to the invention, neighboring pixels extend not only to locations of the same height relative to the direction of extension, or in other words, neighboring pixels extend not only to matching positions with respect to the direction of extension of the row, but also further or beyond them. According to the invention, neighboring pixels of the row each extend next to one another in overlapping regions along the direction of extension of the row. In such overlapping regions of neighboring pixels, radiation can be detected jointly across the neighboring pixels separated from one another by the radiation-insensitive intermediate regions. This enables continuous radiation detection along the direction of extension of the row with a high degree of reliability.

[0029] According to the invention, the pixels in the row have interlocking contours. For example, a stepped interlock is possible. For this purpose, the opposite sides of neighboring pixels can have a stepped profile, as explained above. Another example is a zigzag interlock, which can be achieved using the zigzag profile of opposite sides of neighboring pixels explained above.

[0030] Overlapping areas of adjacent pixels can alternatively also be realized by a configuration in which the opposite sides of adjacent pixels are, for example, rectilinear. In this case, the opposite sides can run parallel to each other and obliquely to the direction perpendicular to the direction of extension, and thus also obliquely to the direction of extension of the row.

[0031] In a further embodiment, the detector is a pixelated photodiode detector. In this embodiment, the detector can be a monolithic semiconductor component and implemented in the form of a semiconductor chip. Such a component can also be referred to as a photodiode array or detector array. In this case, the detector can have a semiconductor layer in which several adjacently arranged photodiodes are formed. Each pixel of the detector can be assigned a corresponding photodiode, or each pixel of the detector can have a corresponding photodiode.

[0032] The semiconductor layer of the photodiode detector can have a layer region with a first, for example, n-type doping, and for each of the photodiodes, a thin front-side layer region with a second doping inverse to the first doping, for example, a p-type doping. This allows each photodiode of the photodiode array formed in the semiconductor layer to have a corresponding pn junction.

[0033] The photodiode detector can further comprise an anti-reflection layer on the front side. Another possible component is the aforementioned shield with cutouts or openings, via which the top-view shapes of the detector's radiation-sensitive pixels, and thus the opposite sides of neighboring pixels as well as the intermediate regions, can be defined. The shield can be arranged on the anti-reflection layer. The front-side layer regions of the photodiodes with the second (for example, p-conductive) doping can have lateral dimensions that match the dimensions of the shield's openings.

[0034] To enable contacting, the photodiode detector can have front-side contacts arranged in the pixel region, which can reach through the antireflection layer to the front-side layer regions of the photodiodes with the second doping. With respect to the other substrate region with the first doping, the photodiode detector can, for example, have a flat back-side contact.

[0035] The detector can comprise a single row of separate pixels arranged side by side. Such a configuration can also be referred to as a 1D arrangement or 1D array. However, configurations with multiple, for example, two parallel rows of separate pixels arranged side by side are also possible, which can also be referred to as a 2D arrangement or 2D array.

[0036] In this sense, according to a further embodiment, the detector comprises a further parallel, offset row of radiation-sensitive pixels arranged next to one another. The pixels of the further row have contours such that opposite sides of adjacent pixels extend at least partially deviating from a perpendicular direction to a direction of extension of the further row. This configuration makes it possible to achieve continuous radiation detection along the direction of extension with respect to the further pixel row as well. Between the pixels of the further row, the detector can also be radiation-insensitive or have radiation-insensitive intermediate regions defined by a shield.

[0037] In a detector configuration with multiple rows of pixels, the pixels of two different rows can also be separated from each other by radiation-insensitive intermediate regions or by a continuous radiation-insensitive intermediate region defined by a detector shield. In this case, the pixels can have contours such that opposite sides of neighboring pixels in the different rows run straight and in the direction of extension of the rows. However, a configuration in which opposite sides of neighboring pixels in the different rows run at least partially deviates from the direction of extension of the rows is also possible.

[0038] According to a further aspect of the invention, a lidar system is proposed. The lidar system comprises a detector with the structure described above or with a structure according to one or more of the embodiments described above. Another component of the lidar system is an emitter for emitting radiation.

[0039] When a lidar system is in operation on a vehicle, the emitter can emit pulsed light. Part of the radiation can be reflected by an object or obstacle and detected spatially by the detector. The detector can generate electrical signals based on the reflected radiation hitting the detector or pixels.

[0040] The detector can be arranged such that the (at least one) pixel row is oriented horizontally. With this orientation, the opposite sides of adjacent pixels (in the case of multiple pixel rows in the respective rows) can at least partially deviate from a vertical direction to the horizontal direction, thus enabling continuous radiation detection with respect to the horizontal direction. This means that columnar obstacles with a small horizontal extension can be reliably detected by the detector based on the reflected radiation.

[0041] The emitter can be configured to emit infrared radiation. For this purpose, the emitter can comprise, for example, an infrared light-emitting laser diode or an infrared light-emitting diode (IRED).

[0042] In addition to the detector and emitter, the lidar system can include other components. For example, an optical system can be connected upstream of the detector. Furthermore, the system can include an evaluation unit to which detector signals from the detector can be transmitted. Based on these signals, the evaluation unit can determine the travel time of the reflected radiation and thus the distance to an obstacle.

[0043] It is noted that embodiments, features and details described above with reference to the detector can also be applied to the lidar system and, conversely, embodiments, features and details described with reference to the system can also be applied to the detector.

[0044] The advantageous embodiments and further developments of the invention explained above and / or reproduced in the subclaims can - except, for example, in cases of clear dependencies or incompatible alternatives - be used individually or in any combination with one another.

[0045] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the schematic drawings. They show: Fig. 1 a schematic representation of a lidar system; Fig. 2 is a plan view of a detector with a row of pixels arranged next to one another and front-side contacts in the form of contact surfaces, with opposite sides of adjacent pixels extending in a stepped manner; Fig. 3 Courses of the local sensitivity of the pixels of the detector of Fig. 2 along the extension direction of the pixel row; Fig. 4 a cross-sectional view of a section of a detector; Fig. 5 is a plan view of another detector having a row of pixels arranged side by side, with opposite sides of adjacent pixels zigzagging; Fig. 6 Plots of the local sensitivity of the pixels of the detector of Fig. 5 along the extension direction of the pixel row; Fig. 7 is a top view of another detector with two rows of pixels arranged next to each other; Fig. 8 is a plan view of another detector with a row of pixels arranged next to one another and front-side contacts, the contacts having a planar and a linear contact section; Fig. 9 is a plan view of another detector with pixels arranged next to one another in a row, with opposite sides of adjacent pixels extending obliquely to the direction of extension of the pixel row; Fig. 10 is a plan view of another detector with pixels arranged next to one another in a row, with adjacent pixels extending to locations with the same height relative to the direction of extension of the pixel row; and Fig. 11 Plots of the local sensitivity of the pixels of the detector of Fig. 10 along the extension direction of the pixel row.

[0046] Based on the following schematic figures, possible embodiments of a detector 100 are described, which can be used in a lidar system 200 (light detection and ranging) for radiation detection. The detector 100 is a pixelated photodiode detector 100, also referred to as a photodiode array or detector array, which has (at least) one row of radiation-sensitive pixels 110 arranged next to one another. The detector 100 is designed such that, despite the pixelated structure, objects with a small horizontal extent can be reliably detected. For this purpose, the pixels 110 of the row have a suitable layout with contours such that, viewed from above, opposite sides of adjacent pixels 110 extend at least partially deviating from a perpendicular direction 151 to an extension direction 150 of the pixel row.

[0047] Please note that the figures are merely schematic and not to scale. As such, components and structures shown in the figures may be exaggerated or reduced in size for clarity. Likewise, it is possible that the detector 100 and the lidar system 200 may include additional components and structures in addition to those shown and described.

[0048] Fig. 1 shows a schematic representation of a lidar system 200. The lidar system 200 is used in a motor vehicle (not shown) to detect objects located in front of the vehicle and their distance from the vehicle. The lidar system 200 comprises an emitter 205, a receiver 210, and an evaluation device 215. The emitter 205 is designed to emit pulsed infrared light radiation 230 into an area in front of the motor vehicle. The emitter 205 can, for example, emit short radiation pulses with a defined length of a few nanoseconds. The emitter 205 can, for example, comprise an infrared light-emitting laser diode or light-emitting diode (IRED) (infrared light-emitting diode).

[0049] The light radiation 230 emitted by the emitter 205 can be reflected by an object 220 located in front of the motor vehicle. The reflected radiation 231, or a portion thereof, can be received by the receiver 210. The receiver 210 comprises a photodiode detector 100 for spatially resolved radiation detection. The detector 100 is designed to generate electrical detector signals 235 as a function of the incident reflected radiation 231, which are transmitted to the evaluation device 215. The receiver 210 can additionally comprise an optical system (not shown) connected upstream of the detector 100, via which the reflected radiation 231 can be directed onto the detector 100.

[0050] The evaluation device 215 is configured to perform a corresponding evaluation using the detector signals 235. This includes determining the propagation time of the radiation pulses reflected by the object 220 and, based on this, determining the distance of the object 220 from the motor vehicle (time-of-flight measurement).

[0051] Fig. 2 shows a top view of a front side of a possible embodiment of a pixelated photodiode detector 100, which in the lidar system 200 of Fig. 1. The detector 100 has a rectangular strip-shaped top view. Viewed from above, the detector 100 has a pixelated structure with a row of several radiation-sensitive pixels 110 arranged next to one another. As shown in Fig. 2, the pixel array of detector 100 may, for example, comprise five pixels 110. The light-sensitive pixels 110 represent the active areas of detector 100, via which radiation detection can occur.

[0052] The detector 100 from Fig. 2 is designed such that the detector 100 is insensitive to light in regions to the side of the pixels 110 or around the pixels 110, and thus also in regions 125 between the pixels 110, which are referred to below as intermediate regions 125. For this purpose, the detector 100 has a front shield 120 with openings 121 assigned to the individual pixels 110 (see also the cross-sectional view of Fig. 4). The contours of the openings 121 determine the contours of the pixels 110, and thus also the top view shapes of the shielded, light-insensitive regions and intermediate regions 125. Unlike the pixels 110, no radiation is detected in the regions and intermediate regions 125 provided with the shield 120. The design of the detector 110 with the intermediate regions 125 separating the pixels 110 ensures, among other things, that crosstalk between the pixels 110 can be suppressed.

[0053] In Fig. 2 also shows front-side contacts 130 of detector 100. These are located at the edge or in the corner area of ​​pixels 110. Contacts 130 are implemented in the form of contact surfaces (in this case, for example, rectangular). Bond wires used to contact detector 100, for example, can be connected to contacts 130 (not shown).

[0054] In Fig. 2, a horizontal arrow additionally indicates an extension direction 150 of the pixel row, along which the pixels 110 are arranged next to one another. Furthermore, a vertical arrow indicates a lateral direction 151 perpendicular to the extension direction 150. With regard to the extension direction 150 and the direction 151 perpendicular thereto, it should be noted that this includes both the directions indicated by the directional arrows and the directions inverse thereto.

[0055] When using the detector 100 of Fig. 2 in the Lidar system 200 of Fig. 1, the detector 100 is positioned with its front side facing the radiation 231 to be detected. Furthermore, the detector 100 is arranged such that the pixel row is oriented horizontally, and thus the extension direction 150 of the row is parallel or congruent with the horizontal direction.

[0056] For the detector 100 of Fig. 2, the pixels 110 defined by the openings 121 of the shield 120 have plan views that differ from a rectangular shape. The pixels 110 have interlocking, in this case step-like, contours. For this purpose, the pixels 110 are designed such that, viewed from above, opposite sides 163 of adjacent pixels 110 each extend in a step-like manner and, in part, deviate from the perpendicular direction 151 to the extension direction 150 of the pixel row.

[0057] Here, the opposing sides 163 of adjacent pixels 110 each have two sections extending perpendicular to the direction of extension 150 or in the direction 151, respectively, and a section extending obliquely thereto between them. These side sections of the stepped sides 163 of adjacent pixels 110 also extend parallel to one another, so that the radiation-insensitive intermediate regions 125 have a linear or strip-like top view. Corresponding to the stepped sides 163, the intermediate regions 125 have a stepped profile that partially deviates from the perpendicular direction 151.

[0058] In contrast, further pixel sides 161, 162 of pixels 110 extend in a straight line. Each pixel 110 has two sides 161 extending in the extension direction 150. The two pixels 110 located at the two ends of the pixel row, which are adjacent to only one pixel 110 and which, compared to the remaining pixels 110, have only one stepped side 163 instead of two stepped sides 163, furthermore have another side 162 at the end of the row that extends in a straight line or in the vertical direction 151.

[0059] Due to the interlocking contours, the pixels 110 extend partially adjacent to one another along the extension direction 150 of the pixel row. Therefore, overlapping regions 155 exist in which a joint radiation detection can occur via two adjacent pixels 110. Fig. In Figure 2, such an overlapping region 155 of two pixels 110 is indicated by dashed lines. This configuration of the detector 100 offers the possibility of avoiding the presence of dead zones along the extension direction 150 of the pixel row. Despite the intermediate regions 125 separating the individual pixels 110, radiation can therefore be detected continuously across the pixels 110 of the detector 100 along the extension direction 150 of the pixel row.

[0060] To further illustrate this property, Fig. 3 Courses 171 of the local radiation sensitivity S of the pixels 110 of the detector 100 of Fig. 2. Each curve 171 represents the sensitivity S of a pixel 110 as a function of a lateral position P along the extension direction 150 of the pixel row. The magnitude of the sensitivity S depends on the width of the pixels 110 relative to the vertical direction 151. The curves 171 are represented in different ways with solid or dashed lines to facilitate assignment to the corresponding pixels 110 of the detector 100.

[0061] Based on Fig. 3 clearly shows that the geometric design of the pixels 110 explained above is associated with a partial overlap of the local sensitivities S of the pixels 110 along the extension direction 150 of the pixel array. The detector 100 thus has overlapping receive channels with respect to the extension direction 150 of the pixel array. This enables continuous radiation detection along the extension direction 150.

[0062] As stated above, the detector 100 comes from Fig. 2 for the Lidar system 200 of Fig. 1 with a horizontal alignment of the pixel row is used. With this alignment, the design of detector 100 enables a horizontal overlap for its channels, so that continuous radiation detection can be achieved with respect to the horizontal direction. In this way, even objects or obstacles with a small horizontal extent can be reliably detected based on the radiation 231 reflected from them and arriving at detector 100. Such obstacles include, for example, columnar obstacles such as people, trees, pillars, etc.

[0063] The pixels 110 of the detector 100 can have lateral dimensions in the range of several hundred microns or even other, for example, larger dimensions. For example, it is possible for the pixels 110 to have dimensions in the range of 600 microns in the direction 150 and in the range of 1000 microns in the direction 151. The intermediate regions 125 can have a width in the range of 10 microns or even another, for example, smaller, width. Such dimensions can also be used for detector layouts described below.

[0064] Fig. Figure 4 shows a cross-sectional view of a section of the pixelated photodiode detector 100, which reveals further details of its structure. The detector 100 is designed as a monolithic semiconductor component or semiconductor chip and has a semiconductor layer 111 in which several adjacently arranged photodiodes are formed. Each pixel 110 is assigned a corresponding photodiode, or each pixel 110 has a corresponding photodiode.

[0065] As in Fig. 4, the semiconductor layer 111 has a layer region 112 with a first doping and, for each of the photodiodes, a thin front-side layer region 113 with a second doping that is inverse to the first doping. For example, it is possible for the layer region 112 to be n-conductive and for the adjacent layer regions 113 to be p-conductive. In this way, each photodiode can have a corresponding pn junction. During operation of the detector 100, this structure can ensure that charge carriers (electron-hole pairs) generated in the semiconductor layer 111 by radiation absorption are separated or can drift into the differently doped layer regions 112, 113, and thus electrical detector signals can be generated.

[0066] The detector 100 further comprises, as shown in Fig. 4, a front-side antireflection layer 115 is arranged on the semiconductor layer 111. With the aid of the antireflection layer 115, reflection of radiation at the front of the detector 100 can be suppressed.

[0067] To pick up the detector signals, the detector 100 has corresponding contacts, via which the layer regions 112, 113 can be contacted. Fig. Figure 4 shows the front-side contacts 130 provided in the area of ​​the pixels 110. The contacts 130 extend through the anti-reflection layer 115 to the layer regions 113 of the photodiodes, allowing contact to be made with the layer regions 113 via these contacts. The contacts 130 can be made of a metallic material.

[0068] For contacting the other layer region 112, the detector 100 may have a further contact (not shown). This may, for example, be a flat contact arranged on a rear side of the detector 100 or the semiconductor layer 111 opposite the front side.

[0069] In Fig. 4 further shows the shield 120 of the detector 100 with the openings 121, via which the contours of the pixels 110 are defined. The shield 120 is arranged on the anti-reflection layer 115. The shield 120 may comprise a metallic material. This may be the same metallic material from which the front-side contacts 130 may be formed. Fig. 4 also indicates that the front layer regions 113 of the photodiodes may have the same lateral dimensions as the openings 121 of the shield 120.

[0070] Deviating from Fig. 4, the detector 100 may optionally have additional layers and / or structures in cross-section. For example, the detector 100 may be formed with an additional oxide layer arranged in the region of the shield 120 between the anti-reflection layer 115 and the semiconductor layer 111.

[0071] In the following, possible modifications or further developments of pixelated photodiode detectors 100 are described, which are also used in the lidar system 200 of Fig. 1 can be used. These detectors 100 are designed according to the previously explained embodiment to enable a gapless radiation detection along the extension direction 150 of a pixel row and thus, when the pixel row is aligned in the horizontal direction, along the horizontal direction. This property is realized in the same way via a suitable geometric design of pixels 110. In this context, it is pointed out that corresponding features and aspects, for example the Fig. 4 will not be described in detail again below. For details, reference is instead made to the above description. Furthermore, it is possible that a feature described with reference to one embodiment may also apply to another embodiment, or that features of multiple embodiments can be combined with one another.

[0072] Fig. Figure 5 shows a top view of a front side of another embodiment of a pixelated photodiode detector 100. The detector 100 has a row of several or five radiation-sensitive pixels 110 arranged adjacently. The contours of the pixels 110 are defined by openings 121 in a front shield 120 of the detector 100.

[0073] For the detector 100 of Fig. 5, the pixels 110 have zigzag-shaped, interlocking contours. For this purpose, the pixels 110 are configured such that, viewed from above, opposite sides 164 of adjacent pixels 110 each have a zigzag shape with sections extending obliquely to the extension direction 150 of the pixel row and to the perpendicular direction 151. The side sections of the zigzag-shaped sides 164 of adjacent pixels 110 further extend parallel to one another, so that the shielded or radiation-insensitive intermediate regions 125 present between the pixels 110 have a strip-shaped, zigzag-shaped top view.

[0074] Further sides 161, 162 of the pixels 110 are rectilinear or extend in the extension direction 150 and, in the case of the sides 162, which are only present at the row ends of the pixels 110, in the vertical direction 151.

[0075] The design of the detector 100 of Fig. 5 with the partially zigzag contours of the pixels 110 makes it possible for all pixels of the row, including the two pixels 110 at the two ends of the row, to have substantially identical dimensions or area dimensions.

[0076] The interlocking contours of the pixels 110 of the detector 100 of Fig. 5 result in the pixels 110 partially extending alongside one another along the extension direction 150 of the pixel row, and therefore overlapping regions 155 are present in which radiation can be detected jointly across two adjacent pixels 110. Despite the intermediate regions 125 separating the pixels 110, continuous radiation detection along the extension direction 150 is consequently possible.

[0077] To illustrate this property, Fig. 6 Courses 172 of the local radiation sensitivity S of the pixels 110 of the detector 100 of Fig. 5 as a function of a lateral position P along the extension direction 150. The geometric design of the pixels 110 leads to a partial overlap of the local sensitivities S of the pixels 110 along the extension direction 150.

[0078] The Fig. 2, Fig. The detectors 100 shown in Figure 5 each have a row of radiation-sensitive pixels 110 arranged side by side. This can also be referred to as a 1D arrangement. However, comparable configurations with multiple offset or parallel pixel rows are also possible. Such a structure can also be referred to as a 2D arrangement.

[0079] A possible example of a detector 100 constructed in this way is shown in plan view in Fig. 7 shown.

[0080] The detector 100 has two parallel rows of several or five pixels 110 arranged next to each other. The pixel rows, which extend along an extension direction 150, are analogous to the pixel row of the detector 100 of Fig. 5. In the individual rows, the pixels 110 therefore have zigzag-shaped, interlocking contours, which is realized by a zigzag-shaped progression of opposite sides 164 of adjacent pixels 110. Therefore, continuous radiation detection along the extension direction 150 is possible in the pixel rows.

[0081] For the detector 100 of Fig. 7, the pixels 110 of the different pixel rows are separated from each other by a shielded, radiation-insensitive intermediate region. Furthermore, rectilinear sides 161 of adjacent pixels 110 of the different rows, extending in the direction 150, are opposite each other.

[0082] A detector 100 with a 2d arrangement of pixels 110 can also be realized with pixels 110 which, for example, have a Fig. 2 or a different shape. Furthermore, such a detector 100 can also be implemented with more than two parallel pixel rows.

[0083] Fig. Figure 8 shows a plan view of a front side of another embodiment of a pixelated photodiode detector 100. The detector 100 has essentially the same structure as that shown in Fig. 2, i.e. a row of pixels 110 with stepped, interlocking contours. Instead of the contacts 130 implemented in the form of contact surfaces, the detector 100 of Fig. 8 front-side contacts 131, each of which, viewed from above, comprises a planar contact section 132 and a linear contact section 133. This configuration can enable a lower electrical resistance compared to the contacts 130. Bonding wires (not shown) can be connected to the planar contact sections 132 of the contacts 131. Similar to the contacts 130, the contacts 131 can extend through a front-side anti-reflection layer 115 to corresponding layer regions 113 of photodiodes (cf. Fig. 4).

[0084] Front-side contacts 131 having planar and linear contact sections 132, 133 can be provided in a corresponding manner in detectors 100, which are Fig. 8 have different designs or forms of view of pixels 100. These include, for example, the previously described Fig. 5, Fig. 7 explained detectors 100.

[0085] A continuous radiation detection along the extension direction 150 of a pixel row can also be realized with the help of pixels 110 in which opposite sides of neighboring pixels 110 are straight. In this sense, Fig. 9 is a plan view of a front side of a further embodiment of a pixelated photodiode detector 100. The detector 100 has a row of several or five radiation-sensitive pixels 110 arranged next to one another, the contours of which are predetermined by openings 121 of a front shield 120 of the detector 100.

[0086] For the detector 100 of Fig. 9, adjacent pixels 110 each have opposite sides 165, which run parallel to one another and obliquely to the extension direction 150 of the pixel row, as well as obliquely to the vertical direction 151. Therefore, the radiation-insensitive intermediate regions 125 present between the pixels 110 have a strip-shaped plan view extending obliquely to the directions 150, 151. Further sides 161, 162 of the pixels 110 also run rectilinearly or extend in the extension direction 150 and, in the case of the sides 162, which are present only at the ends of the pixels 110, in the vertical direction 151.

[0087] For the detector 100 of Fig. 9, the pixels 110 are further spaced apart from one another such that the pixels 110 extend partially adjacent to one another along the extension direction 150 of the pixel row. Consequently, overlapping regions 155 exist in which joint radiation detection can occur across two adjacent pixels 110. This results in continuous radiation detection along the extension direction 150.

[0088] For the detector 100 of Fig. 9, the pixels 110 can have local radiation sensitivities S comparable to the detector 100 of Fig. 5. The Fig. 6 can therefore be used in a corresponding manner for the Fig. The detector layout shown in Figure 9 can be used.

[0089] Continuous radiation detection is also possible without overlapping or intersection areas 155 of neighboring pixels 110. In this sense, Fig. 10 is a plan view of a front side of another embodiment of a pixelated photodiode detector 100. The detector 100 has essentially the same structure as that shown in Fig. 2, i.e. a row of pixels 110, wherein the opposite sides 163 of adjacent pixels 110 and the radiation-insensitive intermediate regions 125 therebetween have a stepped shape. In comparison to the detector 100 of Fig. 2, however, the pixels 110 are arranged at a greater distance or such a distance that the pixels 110 on the sides 163 extend to locations which have matching heights with respect to the extension direction 150 of the row, or in other words, that the pixels 110 on the sides 163 extend to matching positions with respect to the extension direction 150 of the row. This is shown in Fig. 10 for two pixels 110 indicated by a dashed line.

[0090] The Fig. The embodiment of the detector 100 shown in Figure 10 also offers the possibility of achieving continuous radiation detection along the extension direction 150 of the pixel row, wherein radiation can be detected alternately across the pixels 110. To illustrate this property, Fig. 11 Courses 173 of the local radiation sensitivity S of the pixels 110 as a function of a lateral position P along the extension direction 150. Based on Fig. 11 it becomes clear that the design of the detector 100 of Fig. 10 is connected to adjacent local sensitivities S of the pixels 110 along the extension direction 150 of the pixel row.

[0091] The embodiments explained with reference to the figures represent preferred or exemplary embodiments of the invention. In addition to the described and illustrated embodiments, further embodiments are conceivable, which may include further modifications and / or combinations of features. For example, it is possible to replace the above numerical specifications with other specifications. In this respect, pixels 110 can be formed with lateral dimensions other than those mentioned above. Detectors 100 can also be implemented with different numbers of pixels 110 arranged next to one another in a row, as well as with different numbers of parallel pixel rows.

[0092] Further possible modifications consist in realizing pixels 110 with geometric top view shapes or contours that deviate from the contours described and shown in the figures.

[0093] In this sense, it may be considered that the contours of the pixels 110 are at least partially curved. For example, at the points where the contours are curved according to the Fig. 2, Fig. 5, Fig. 7, Fig. 8, Fig. 9, Fig. 10 have tapered sections, a round or curved contour section may be provided. This can suppress the occurrence of an increased electric field strength.

[0094] With regard to a 2D design of a detector 100 with multiple pixel rows, one possible modification is to design pixels 110 with contours such that opposite sides of adjacent pixels 110 of different rows extend at least partially deviating from the extension direction 150 of the pixel rows. In this case, it can be provided that the pixels 110 of different pixel rows have interlocking contours. In this way, overlapping reception channels or continuous radiation detection can also be provided in the direction 151 perpendicular to the extension direction 150.

[0095] Although the invention has been illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

[1] Detector (100) for a lidar system (200), comprising a row of radiation-sensitive pixels (110) arranged side by side, wherein the pixels (110) of the row have contours such that opposite sides (163, 164, 165) of adjacent pixels (110) extend at least partially deviating from a perpendicular direction (151) to an extension direction (150) of the row, wherein adjacent pixels (110) of the row each extend next to one another in overlapping regions (155) along the direction of extension of the row, and wherein the pixels (110) of the row have interlocking contours. [2] A detector according to claim 1, wherein the opposite sides (163) of adjacent pixels (110) of the row are stepped. [3] A detector according to any preceding claim, wherein the opposite sides (164) of adjacent pixels (110) of the row are zigzag. [4] Detector according to one of the preceding claims, comprising a front shield (120) with a plurality of openings (121) associated with the pixels (110). [5] Detector according to claim 4, wherein the contours of the pixels (110) are predetermined by the contours of the openings (121) of the shield (120). [6] Detector according to one of the preceding claims, comprising radiation-insensitive intermediate regions (125) between the pixels (110) by which the pixels (110) are separated from one another. [7] A detector according to any one of the preceding claims, wherein the detector is a pixelated photodiode detector. [8] Detector according to one of the preceding claims, comprising a further parallel offset row of radiation-sensitive pixels (110) arranged next to one another, wherein the pixels (110) of the further row have contours such that opposite sides (164) of adjacent pixels (110) extend at least partially deviating from a perpendicular direction (151) to an extension direction (150) of the further row. [9] Lidar system (200) comprising a detector (100) according to one of the preceding claims and an emitter (205) for emitting radiation (230).

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