JPH11145509A - Semiconductor position sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor position sensor having superior detection characteristic of the place of light incidence and improving the accuracy of distance measurement at a long distance at usage for a distance measurement equipment. SOLUTION: Conductive layers 4 are formed to the light-receiving surface 21 of a semiconductor substrate 2 and currents, corresponding to the places of light incidence are output through the conductive layers 4 by the incidence of light to the light-receiving surface 21 in the semiconductor position sensor, the conductive layers 4 are formed into a linear shape and extended, while being folded back to the left and the right on the light-receiving surface, and the width of the conductive layers 4 becomes larger in the longitudinal direction of the conductive layers 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor position detector capable of detecting a light incident position and used for a distance measuring device or the like.

[0002]

2. Description of the Related Art A semiconductor position detector (PSD) is known as an apparatus for measuring the distance of an object to be measured by using the so-called triangulation principle or the like. The PSD is mounted on an imaging device such as a camera as an active distance measuring device, and in such an imaging device, focusing of a photographic lens is performed based on a distance of an object to be measured measured by the PSD.

[0003]

In the above-mentioned PSD, the position of the incident light spot on the light receiving surface of the PSD moves according to the distance to the object to be measured. Since the charge generated by light incident on the PSD is divided almost in inverse proportion to the resistance from the incident position to the electrodes at both ends of the resistive layer, the output current from the PSD changes according to the incident light spot position, The distance to the device under test can be detected based on the output current. However, when performing distance measurement using the principle of triangulation, when the distance to the object at a short distance changes, the position of the incident light spot moves greatly on the light receiving surface, while When the distance to a certain object changes, the position of the incident light spot does not change much. That is, conventionally, the accuracy of detecting a distance to an object to be measured at a long distance is low compared to the accuracy at a short distance. Therefore, by making the width of the resistive layer irradiated with the incident light spot linearly smaller from the near side to the far side of the light receiving surface, the incident light spot from the object at a long distance is reduced. Japanese Patent Application Laid-Open No. 4-240511 discloses a configuration in which the resistance division ratio of the resistance layer is largely changed even if the amount of movement is small.

However, in the PSD described in the publication, the width of the resistance layer is increased linearly from the long distance side to the short distance side, that is, the resistance layer is increased from the short distance side to the long distance side. As it goes, it becomes narrower in a linear function. This resistance layer forms a light receiving surface. The resistance layer can be considered as a minute resistance aggregate in which minute resistances are connected in a matrix. The charge generated by light incident on the resistive layer is divided in inverse proportion to each resistance value from the incident position to the electrodes at both ends of the resistive layer, but only a part of the minute resistance group aligned in the resistive layer width direction When the spot-shaped incident light is irradiated, the generated charges do not pass uniformly along the length direction of the resistive layer, and therefore the incident light position and output theoretically calculated from the shape of the resistive layer The relational expression with the current differs for each incident light position and incident light shape, and it is difficult to accurately calculate the incident light position from the output current using a single relational expression. That is, in order to obtain an accurate incident light position from the output current, a plurality of arithmetic circuits different for each incident light position and incident light shape are required. In other words, in the above-mentioned conventional PSD, when the incident light is applied to all of the minute resistance groups aligned in the resistance layer width direction,
That is, the position of the incident light can be obtained by using a single arithmetic circuit only when the slit-shaped incident light is incident so as to traverse the resistance layer.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and can improve the position detection accuracy as compared with the prior art, and has no limitation on the shape of the incident light. The purpose is to provide.

[0006]

In order to achieve the above object, a semiconductor position detector according to the present invention has a conductive layer formed on a light receiving surface of a semiconductor substrate, and a conductive layer is formed by light incident on the light receiving surface. In a semiconductor position detector that outputs a current according to its incident position through a layer, the conductive layer is a linear body that extends while folding right and left on the light receiving surface, and the width of the conductive layer extends along the longitudinal direction. It is characterized by being.

Further, the semiconductor position detector according to the present invention is characterized in that the width dimension of the conductive layer is widened as a function of the first order or more and the second order or less with respect to the length dimension of the conductive layer in the longitudinal direction.

Further, in the semiconductor position detector according to the present invention, the electric charge passing through the semiconductor region adjacent to one end portion having the narrowest width of the conductive layer and the semiconductor region in response to incident light flows without passing through the conductive layer. And a signal extraction electrode provided at a position capable of taking out one of the output currents.

According to these inventions, since the conductive layer is a linear body having a small width, an output according to a resistance value determined by a shape of the conductive layer from a light incident position to each signal extraction electrode is obtained. , Without depending on the shape of the incident light. Further, when compared with the PSD described in JP-A-4-240511 in which the conductive layer (resistive layer) is the same as the light receiving surface, the conductive layer has a narrow width and a long length. Even if the rate is lowered, a desired resistance value can be obtained. That is, by increasing the impurity concentration, the ratio of the minimum controllable impurity concentration to the entire impurity concentration is reduced, so that the variation in resistivity is reduced and the position detection accuracy is improved. Therefore, when used in a distance measuring device or the like, the distance measuring performance is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described below with reference to the accompanying drawings. In the drawings, the same elements are denoted by the same reference numerals, and the description is omitted. Also,
The dimensional ratios in the drawings do not always match those described.

(First Embodiment) FIG. 1A is a plan view of a semiconductor position detector (hereinafter referred to as "PSD") 1 according to a first embodiment. FIG. 1 (b) is the same as FIG.
It is sectional drawing of PSD1 in II. The cross-sectional view of the PSD used for the description shows the end face.

In FIG. 1B, the PSD 1 has a semiconductor substrate 2 made of low-concentration n-type Si. The semiconductor substrate 2 has a rectangular shape when viewed from a plane as shown in FIG. Formed. The back side of the semiconductor substrate 2 (FIG. 1)
A semiconductor layer 3 made of high-concentration n-type Si is provided on the lower side in FIG. The semiconductor substrate 2 of the PSD 1
Is a light receiving surface 21 on which light to be detected is incident, and the light receiving surface 21 is provided with a conductive layer 4.

As shown in FIG. 1A, the conductive layer 4 is a flow path of a current generated by light incident on the light receiving surface 21 and is inversely proportional to each resistance value from the incident position to both ends. The current is divided as described above, and is formed of, for example, p-type Si, and the resistivity of the conductive layer 4 is lower than the resistivity of the semiconductor substrate 2. The conductive layer 4 is provided on the light receiving surface 2.
1 is a linear body that extends while being folded right and left. For example, as shown in FIG. 1 (a), it extends so as to extend longitudinally through the light receiving surface 21, and is folded right and left in the extending direction to form a zigzag line.

The conductive layer 4 has a substantially uniform resistivity in each region, and as shown in FIG. 1B, its dimension in the depth direction is substantially constant. Since the conductive layer 4 is formed in a narrow linear shape, a desired resistance value can be obtained even if the impurity concentration of the conductive layer 4 is increased to lower the resistivity. That is, by increasing the impurity concentration, the ratio of the minimum controllable impurity concentration to the entire impurity concentration is reduced, so that the variation in resistivity is reduced and the position detection accuracy is improved.

Further, the conductive layer 4 is formed such that its width increases along its longitudinal direction. For example, FIG.
As shown in FIG. 1A, the width of the conductive layer 4 increases from one side to the other side (from left to right in FIG. 1A).
The width dimension of the conductive layer 4 expands as a linear function with respect to the dimension in the longitudinal direction. When the relationship of a higher-order function such as a third-order or fourth-order function is satisfied, a change in the width dimension with respect to a change in the length dimension on the narrow side of the conductive layer 4 is extremely small, and the width dimension is controlled with extremely high precision. Therefore, if the conductive layer 4 is manufactured with normal manufacturing accuracy, the position detection accuracy will deteriorate. Further, in order to obtain the position detection accuracy required for normal manufacturing accuracy, it is necessary to increase the width dimension.
SD1 must be very large. On the other hand, when the relationship of the first-order or more-second-order function is satisfied, the conductive layer 4
The change in the width dimension with respect to the change in the length dimension on the narrow side is large. Therefore, even if the conductive layer 4 is manufactured with normal manufacturing accuracy, the rate of change of the width dimension with respect to manufacturing accuracy is large.
The required properties can be obtained. Therefore, it is desirable that the conductive layer 4 be provided such that the width dimension thereof is expanded in a function of a first order or more and a second order or less with respect to the longitudinal dimension of the conductive layer 4. That is, the width dimension of the conductive layer 4 is Y, the length dimension of the conductive layer is X, and the width dimension Y of the conductive layer 4 is Y = aX ⁿ + b (a
And b are constants), it is preferable that 1 ≦ n ≦ 2. The width of the conductive layer 4 is not limited to one having a smooth width, but may be a case where the width gradually increases along the longitudinal direction.

In FIG. 1B, the semiconductor substrate 2 of the PSD 1 is provided with semiconductor layers 51 and 52 for signal extraction. The signal extraction semiconductor layers 51 and 52 are made of high-concentration p-type S
i. Further, the signal extraction semiconductor layer 5
1 is connected to the wider end of the conductive layer 4, and the signal extraction semiconductor layer 52 is connected to the narrower end of the conductive layer 4. The signal extraction semiconductor layers 51 and 52 extend downward from the surface of the semiconductor substrate 2 to a position deeper than the depth of the conductive layer 4.

As shown in FIG. 1, the PSD 1 is provided with signal extraction electrodes 61 and 62. Signal extraction electrode 6
Reference numerals 1 and 62 denote electrodes for extracting output currents from both ends of the conductive layer 4, formed above the semiconductor substrate 2 and connected to the signal extraction semiconductor layers 51 and 52, respectively. Further, as shown in FIG. 1, the PSD 1 is provided with an outer frame semiconductor layer 22 at an outer edge portion of the light receiving surface 21 of the semiconductor substrate 2. The outer frame semiconductor layer 22 is formed of high-concentration n-type Si, and has a conductive layer 4 and a signal extraction semiconductor layer 5.
It surrounds the substrate surface region where the first and second 52 are formed, and extends downward from the surface of the semiconductor substrate 2 to a predetermined depth.

As shown in FIG. 1, the PSD 1 is provided with an outer frame electrode 63. The outer frame electrode 63 is for preventing disturbance light from entering the semiconductor substrate 2 from outside the PSD 1. Further, the outer frame electrode 63 is in ohmic contact with the outer frame semiconductor layer 22, and the PSD 1 can be operated by applying a predetermined voltage between the outer frame electrode 63 and the signal extraction electrodes 61, 62. . FIG. 1 (b)
As shown in FIG. 1, a passivation film 7 is provided on the semiconductor substrate 2 of the PSD 1. Passivation film 7
Is a film for covering the light receiving surface 21 and protecting the conductive layer 4 and the like. In FIG. 1A, the illustration of the passivation film 7 is omitted for convenience of explanation.

Further, as shown in FIG.
The electrode 64 is provided on the back surface of the substrate, and is in ohmic contact with the back surface side n-type semiconductor layer 3.

In the PSD 1 according to the present embodiment, by providing the conductive layer 4 having a narrow width in a zigzag shape, the incident position of the incident light can be accurately detected without being affected by the shape of the incident light. Accuracy can be improved over conventional PSDs.

Next, a method of using the PSD 1 and its operation will be described.

FIG. 2 shows a distance measuring apparatus using PSD1.
This distance measuring device is installed in an imaging device such as a camera and used for measuring the distance to a subject.
Light emitting diode (LED) 101 and light emitting lens 10
2, a condenser lens 103, and an arithmetic circuit 104. The LED 101 emits light to a distance measurement target such as a subject, and is arranged at a predetermined distance from the PSD 1. The PSD 1 has a signal extraction electrode 6
By applying a predetermined voltage between the electrodes 1 and 62 and the electrode 64, a reverse bias is applied to the pn junction diode formed of the conductive layer 4 and the semiconductor substrate 2. In the PSD 1, the direction in which the conductive layer 4 extends (the horizontal direction in FIG.
It is arranged so as to be parallel to a line segment defined by the distance (base line length) B between the optical axis 02 and the lens 103. Further, the signal extracting electrode 62 is arranged so as to be closer to the optical axis of the lens 103 than the signal extracting electrode 61. Furthermore,
The distance f between the lenses 102 and 103 and the light receiving surface 21 of the PSD 1 is substantially equal to the focal length of the lenses 102 and 103. In addition, on the optical axis of the condenser lens 103, the light receiving surface 21 corresponding to the end of the conductive layer 4 closest to the signal extraction electrode 62 is located.

In this state, when the object to be measured is irradiated with the infrared light emitted from the LED 101 through the light projecting lens 102, the reflected light from the object to be measured is
3 and is incident on the light receiving surface 21 of the PSD 1. And
When light is incident on the light receiving surface 21, a hole-electron pair (charge) is generated inside the PSD 1 in accordance with the incidence of the light, and one of them is placed in the conductive layer 4 according to diffusion and an electric field inside the PSD 1. Flow in. Then, the charge is distributed from the light incident position on the light receiving surface 21 through the conductive layer 4 and is extracted as an output current from the signal extraction electrode 61 and the signal extraction electrode 62.

At this time, in FIG. 2, when the infrared light emitted from the LED 101 irradiates the object OB1 located at a short distance (L1) via the light projecting lens 102, the object OB1 receives the infrared light. The reflected light is transmitted through the condenser lens 103 to P
The light enters the near side of the light receiving surface 21 of the SD 1, that is, the side near the signal extraction electrode 61. On the other hand, LED1
When the infrared light 01 is irradiated on the object OB2 located at a long distance (L2), the reflected light from the object OB2 located at a long distance (L2) is received by the PSD 1 via the condenser lens 103. The light is incident on the far side of the surface 21, that is, on the side closer to the signal extraction electrode 62. Here, it is assumed that the end position of the conductive layer 4 on the signal extraction electrode 62 side is a reference position, and the incident position of the light reflected by the object OB1 at a short distance is a position separated by a distance X1 from the reference position. Further, it is assumed that the incident position of the light reflected by the object to be measured OB2 at a long distance is a position separated by a distance X2 from the reference position.
Let C be the distance between the two ends of
(L1, L2) and incident light spot position X (X1, X2)
Is a relation given by the following equation.

[0025]

(Equation 1)

Further, the distance L (L1, L1,
FIG. 3 specifically shows the relationship between L2) and the incident light spot position X (X1, X2). In the PSD 1 of the present embodiment, the base length B is 30 mm and the focal length f is 15 mm.

As shown in FIG. 3, as the distance L increases, the incident light spot position X with respect to the variation of the distance L
Becomes smaller. On the other hand, the width dimension of the conductive layer 4 and the length dimension of the conductive layer 4 are, as described above, Y = aX
+ B. That is, the width of the conductive layer 4 is
This is a linear function of a position from one end of the conductive layer 4 along the length direction of the conductive layer 4. In this case, the incident light spot position X and the relative photocurrent output (%) have the relationship shown in FIG. In FIG. 4, I1 is a current output from the signal extraction electrode 62 through the conductive layer 4 due to the incidence of light, and I2 is a current output from the signal extraction electrode 61 through the conductive layer 4 due to the incidence of light. Further, the distance C of the conductive layer 4 is set to 1000 μm.
And the width Y and the position (dimension in the longitudinal direction) X are Y = 0.
It is assumed that 1X + 10 (μm) is satisfied. The photocurrent relative output means output currents I1 and I1 from both ends of the conductive layer 4.
2 to the total output current I1 + I2.

When the ratios R1 = I1 / (I1 + I2) and R2 = I2 / (I1 + I2) are calculated, the incident light spot position X is obtained by the following equation.

[0029]

(Equation 2)

The arithmetic circuit 104 calculates the ratios R1 and R2 from the output currents I1 and I2, then calculates the position X, and stores a table showing the relationship between the distance L and the position X calculated in advance. The distance L can be obtained by searching for the distance L corresponding to the position X in. In addition,
Since the incident light position X has the following relationship, the position L may be calculated from the above expression after directly calculating the position X from the following expression.

[0031]

(Equation 3)

(Second Embodiment) Next, a semiconductor position detector according to a second embodiment will be described.

FIG. 5 shows a PSD 1a according to this embodiment. FIG. 5A is a plan view of the PSD 1a, and FIG. 5B is a cross-sectional view taken along a line VV in FIG. 5A. PSD1a is
A plurality of conductive layers 4 provided on a light receiving surface 21;
As shown in FIG. 5A, for example, two conductive layers 4a and 4b are provided on the light receiving surface 21. Conductive layers 4a, 4b
Is formed in the same shape as the conductive layer 4 of the first embodiment. In the PSD 1a according to the present embodiment, the number of the conductive layers 4 is not limited to two, but may be three or more. In FIG. 5A, the conductive layer 4a and the conductive layer 4b are separated from each other by the semiconductor substrate 2 and the semiconductor layer 23 on the light receiving surface 21, but the folded portions where the adjacent conductive layers 4a and 4b approach each other. 41, 41 may be connected.

According to the PSD 1a, in addition to the same effects as those of the PSD 1 of the first embodiment, an effect that the light receiving surface 21 can be enlarged by adding the conductive layer 4 can be obtained.

(Third Embodiment) Next, a semiconductor position detector according to a third embodiment will be described.

FIG. 6 shows a PSD 1b according to this embodiment. FIG. 6A is a plan view of the PSD 1b, and FIG. 6B is a cross-sectional view taken along the line VI-VI of FIG. PSD1b
Has a plurality of conductive layers 4 provided on a light receiving surface 21. For example, as shown in FIG. 6A, two conductive layers 4a and 4b are provided on the light receiving surface 21. This PSD1b
Has substantially the same structure as the PSD 1a of the second embodiment, but differs from the PSD 1a in that the folded directions of the conductive layers 4a and 4b are the same. This conductive layer 4
a and 4b are formed in the same shape as the conductive layer 4 of the first embodiment. The number of the PSDs 1b is not limited to two, and may be three or more.

According to such a PSD 1b, in addition to the effect similar to that of the PSD 1 of the first embodiment, an effect that the light receiving surface 21 can be enlarged by adding the conductive layer 4 can be obtained.

(Fourth Embodiment) Next, a semiconductor position detector according to a fourth embodiment will be described.

FIG. 7 shows a PSD 1c according to this embodiment. FIG. 7A is a plan view of the PSD 1c, and FIG. 7B is a cross-sectional view taken along line VII-VII of FIG. 7A. PSD1c
Is provided with a conductive layer 4 extending on the light receiving surface 21 while being folded back, and has a structure substantially similar to the PSD 1 of the first embodiment. The PSD 1c according to the first embodiment is different from the first embodiment in that the signal extraction semiconductor layers 51c and 52c are formed simultaneously with the conductive layer 4 and formed at the same depth as the conductive layer 4.
Different from D1.

According to the PSD 1c, in addition to the same effects as those of the PSD 1 of the first embodiment, the effect that the manufacturing efficiency can be improved by reducing the number of manufacturing steps can be obtained.

(Fifth Embodiment) Next, a semiconductor position detector according to a fifth embodiment will be described.

FIG. 8 shows a PSD 1d according to this embodiment. 8A is a plan view of the PSD 1d, and FIG. 8B is a cross-sectional view taken along line VIII-VIII of FIG. 8A. PSD1
“d” is provided with the conductive layer 4 that extends while being folded on the light receiving surface 21 and has a structure substantially similar to that of the PSD 1 of the first embodiment. The PSD 1d has signal extraction semiconductor layers 51d and 52d without the signal extraction electrodes 61 and 62 immediately above the portion in contact with both ends of the conductive layer 4 by a predetermined distance.
Is different from the PSD 1 of the first embodiment.

According to the PSD 1d, the same effects as those of the PSD 1 of the first embodiment can be obtained. Also,
In the PSD 1 of the first embodiment, when the spot light is incident on the end side of the conductive layer 4, a part of the incident light is changed to the signal extraction electrode 61,
62, the position of the center of gravity of the incident light is shifted according to the blocked portion.
In this case, even in such a case, it is possible to collect the charges generated in accordance with the incident light in the signal extraction semiconductor layers 51d and 52d, and it is possible to further improve the position detection accuracy.

(Sixth Embodiment) Next, a semiconductor position detector according to a sixth embodiment will be described.

FIG. 9 shows a PSD 1e according to this embodiment. 9A is a plan view of the PSD 1e, and FIG. 9B is a cross-sectional view taken along line IXb-IXb of FIG. 9A. FIG. 9 (c)
FIG. 10 is a sectional view taken along line IXc-IXc of FIG. PSD
Reference numeral 1e denotes a light-receiving surface 21 provided with a conductive layer 4 that extends while being folded back, and has substantially the same structure as the PSD 1 of the first embodiment. This PSD 1e is a conductive layer 4
Are different from the PSD 1 of the first embodiment in that semiconductor layers 51e and 52e independent of the conductive layer 4 are provided at both ends of the semiconductor device and connected by signal extraction electrodes 61e and 62e, respectively.

According to the PSD 1e, the same effects as those of the PSD 1 of the first embodiment can be obtained. Also,
Similar to the PSD 1d according to the fifth embodiment, the position detection accuracy at the end of the conductive layer 4 can be further improved.

(Seventh Embodiment) Next, a semiconductor position detector according to a seventh embodiment will be described.

In the PSDs of the first to sixth embodiments described above, the conductive layers 4 to 4b have a zigzag shape, but the conductive layers 4 to 4b have such a shape. However, the shape is not limited to this, and may be any other shape as long as it extends while being folded right and left on the light receiving surface 21 and its width extends along the longitudinal direction. Therefore, the PSD 1f according to the present embodiment is formed by folding the conductive layer in a crank shape.

FIG. 10 shows a PSD 1f according to the present embodiment. FIG. 10A is a plan view of the PSD 1f, and FIG.
FIG. 11 is a sectional view taken along line X-X in FIG. PSD1
f is provided with a conductive layer 4f that extends while being folded back on the light receiving surface 21, and has substantially the same structure as the PSD 1 of the first embodiment. The PSD 1f is different from the PSD 1f of the first embodiment in that the PSD 1f includes a conductive layer 4f bent in a crank shape.
Different from SD1. Although FIG. 10 shows an example in which the PSD 1 of the first embodiment is modified, the conductive layers of the PSDs 1a to 1e of the second to sixth embodiments may be formed in a crank shape in the same manner.

[0050] Also in such a PSD 1f, the same operation and effect as those of the PSDs 1 to 1e of the first to sixth embodiments can be obtained.

(Eighth Embodiment) Next, a semiconductor position detector according to an eighth embodiment will be described.

FIG. 11 shows a PSD 1g according to the present embodiment. FIG. 11A is a plan view of the PSD 1g, and FIG.
FIG. 12 is a sectional view taken along line XI-XI of FIG. PSD
1 g is a conductive layer 4 g extending while being folded back on the light receiving surface 21.
Are provided, and have substantially the same structure as the PSD 1 of the first embodiment. The PSD 1g differs from the PSD 1 of the first embodiment in that the left and right folded portions 41 in the conductive layer 4g have a smooth curved shape. Although FIG. 11 shows an example in which the PSD 1 of the first embodiment is modified, similarly, the folded portions of the conductive layers in the PSDs 1a to 1f of the second to seventh embodiments may be curved. .

Even with such a PSD 1g, the same operation and effect as those of the PSDs 1 to 1f of the first to seventh embodiments can be obtained.

[0054]

As described above, according to the present invention, since the incident position of light is detected by the output current outputted from the narrow conductive layer, the incident light theoretically calculated from the shape of the conductive layer is obtained. The relational expression between the position and the output current does not change for each incident light position and incident light shape. Therefore, the incident light position can be accurately calculated from the output current by using a single relational expression, and a plurality of different arithmetic circuits are not required for the incident light position and the incident light shape as in the related art.

Further, by making the linear portion of the conductive layer a function of first order or more and second order or less, accurate position detection can be performed even in manufacturing with normal manufacturing accuracy, and the position to be measured at a long distance measurement can be measured. The change in the resistance division ratio of the conductive layer with respect to the moving amount of the incident light from the object is large, and the calculation of the incident light position from the output current is easy.

Further, according to the present invention, since a desired resistance value can be obtained by increasing the impurity concentration, variation in the resistance value is reduced, and the position detection accuracy can be improved. Therefore, there is no limitation on the shape of the incident light, and the position of the incident light can be accurately and easily calculated from the output current using a single relational expression. Can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a semiconductor position detector according to a first embodiment.

FIG. 2 is an explanatory diagram of a method of using a semiconductor position detector.

FIG. 3 is a diagram showing a relationship between an incident light spot position and a measurement distance in a semiconductor position detector.

FIG. 4 is a diagram showing a relationship between an incident light spot position and a photocurrent relative output in the semiconductor position detector according to the present invention.

FIG. 5 is an explanatory diagram of a semiconductor position detector according to a second embodiment.

FIG. 6 is an explanatory diagram of a semiconductor position detector according to a third embodiment.

FIG. 7 is an explanatory diagram of a semiconductor position detector according to a fourth embodiment.

FIG. 8 is an explanatory diagram of a semiconductor position detector according to a fifth embodiment.

FIG. 9 is an explanatory diagram of a semiconductor position detector according to a sixth embodiment.

FIG. 10 is an explanatory diagram of a semiconductor position detector according to a seventh embodiment.

FIG. 11 is an explanatory diagram of a semiconductor position detector according to an eighth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor position detector, 2 ... Semiconductor substrate, 21 ... Light receiving surface, 4 ... Conductive layer

Claims (3)

[Claims] 1. A semiconductor position detector having a conductive layer formed on a light receiving surface of a semiconductor substrate and outputting a current according to the incident position through the conductive layer when light is incident on the light receiving surface, wherein the conductive layer is A linear body extending while being folded right and left on the light receiving surface, wherein a width of the conductive layer is widened along a longitudinal direction thereof. 2. The semiconductor position according to claim 1, wherein a width dimension of said conductive layer is widened as a function of a first order or more and a second order or less with respect to a longitudinal length of said conductive layer. Detector. 3. A semiconductor region adjacent to one end of the conductive layer having the narrowest width, and a position where charges passing through the semiconductor region according to the incident light can flow without passing through the conductive layer. And a signal extraction electrode from which one of the output currents is extracted.
A semiconductor position detector according to claim 1.