Photodetector based on buried junctions and a corresponding method of manufacture
First Claim
Patent Images
1. A photodetector based on buried junctions comprising:
- a semiconductor structure (10,
110) having a surface (30,
130), and including at least two successive p-n junctions (11, 12, 111-113) buried at increasing depths (P1, P2, P'"'"'1-P'"'"'3), assembled in pairs in opposition and defining at least three layers (21-23, 121-124), one of said layers (21,
121) being adjacent to a photosensitive part (34,
131) of the surface (30,
130), each of said layers (21-23, 121-124) emerging onto a respective part (31-33, 131-134) of the surface (30,
130),an external circuit (40-140) connected to said parts (31-33, 131-134) of the surface (30,
130), said external circuit passing external currents (I1, I1.2, I'"'"'1, I'"'"'1.2, I'"'"'2.3) between the layers (21-23, 121-124),means (44, 45, 145-147) for applying reverse bias to the junctions (11, 12, 111-113) comprising voltage generators (44, 45, 145-147) arranged in said external circuit (40,
140), andmeans (50,
150) for detecting intensities of at least two internal currents (I1, I2, I'"'"'1 -I'"'"'3) passing respectively through said junctions (11, 12, 111-113), said means (50,
150) for detecting being connected to said external circuit (40,
140), said internal currents (I1, I2, I'"'"'1 -I'"'"'3) being generated by the reception of light (5) on the photosensitive part (34,
131), each of the junctions (11, 12, 111-113) being associated respectively with one peak wavelength (l1, l2, l'"'"'1 -l'"'"'3) of the light (5), the intensity of the internal current (I1, I2, I'"'"'1 -I'"'"'3) passing through said junction (11, 12, 111-113) having a peak centered on said peak wavelength for a constant luminous power, the external currents (I1, I1.2, I'"'"'1.2, I'"'"'2.3)comprising combinations of the internal currents (I1, I2, I'"'"'1 -I'"'"'3).
2 Assignments
0 Petitions
Accused Products
Abstract
A photodetector based on buried junctions includes a semiconductor structure with two successive p-n junctions, buried at increasing depths, assembled in pairs in opposition, and defining at least three layers. One of the layers is adjacent to a photosensitive portion of the surface of the photodetector. A reverse bias is applied to the junctions, and the values of at least two internal currents passing through such junctions is detected. The internal currents are generated by received light, with each of the junctions corresponding to a particular wavelength of the received light.
-
Citations
18 Claims
-
1. A photodetector based on buried junctions comprising:
-
a semiconductor structure (10,
110) having a surface (30,
130), and including at least two successive p-n junctions (11, 12, 111-113) buried at increasing depths (P1, P2, P'"'"'1-P'"'"'3), assembled in pairs in opposition and defining at least three layers (21-23, 121-124), one of said layers (21,
121) being adjacent to a photosensitive part (34,
131) of the surface (30,
130), each of said layers (21-23, 121-124) emerging onto a respective part (31-33, 131-134) of the surface (30,
130),an external circuit (40-140) connected to said parts (31-33, 131-134) of the surface (30,
130), said external circuit passing external currents (I1, I1.2, I'"'"'1, I'"'"'1.2, I'"'"'2.3) between the layers (21-23, 121-124),means (44, 45, 145-147) for applying reverse bias to the junctions (11, 12, 111-113) comprising voltage generators (44, 45, 145-147) arranged in said external circuit (40,
140), andmeans (50,
150) for detecting intensities of at least two internal currents (I1, I2, I'"'"'1 -I'"'"'3) passing respectively through said junctions (11, 12, 111-113), said means (50,
150) for detecting being connected to said external circuit (40,
140), said internal currents (I1, I2, I'"'"'1 -I'"'"'3) being generated by the reception of light (5) on the photosensitive part (34,
131), each of the junctions (11, 12, 111-113) being associated respectively with one peak wavelength (l1, l2, l'"'"'1 -l'"'"'3) of the light (5), the intensity of the internal current (I1, I2, I'"'"'1 -I'"'"'3) passing through said junction (11, 12, 111-113) having a peak centered on said peak wavelength for a constant luminous power, the external currents (I1, I1.2, I'"'"'1.2, I'"'"'2.3)comprising combinations of the internal currents (I1, I2, I'"'"'1 -I'"'"'3). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method of spectral measurement comprising the steps of:
-
sending light (5) having an intensity centered on a centering wavelength onto a photosensitive part (34) of a surface (30) of a semi-conductor structure (10), said structure (10) including two successive p-n junctions (11,
12) buried at increasing depths (P1, P2), assembled in pairs, in opposition and defining three layers (21-23), one of said layers (21) being adjacent to the photosensitive part (34) and each of the junctions (11,
12) having a reverse bias, each of said layers (21-23) emerging onto a respective part (31-33, 131-134) of the surface (30), an external circuit (40-140) connected to said parts (31-33, 131-134) of the surface (30,
130) said external circuit passing external currents (I1, I1.2, I'"'"'1, I'"'"'1.2, I'"'"'2.3) between the layers (21-23, 121-124), said reverse bias being supplied by voltage generators (44, 45, 145-147) arranged in said external circuit (40,
140),measuring internal currents (I1, I2) respectively passing through said junctions (11,
12) and being generated by the sending of the light (5) using measuring means connected to said external circuit, each of the internal currents (I1, I2) having, for constant luminous power, an intensity peak centered on a wavelength (l1, l2) of the light (5), called the peak wavelength,calculating a value of the ratio (r) of the intensities of the two internal currents (I1, I2), and extracting said centering wavelength from a reference curve (86) giving the spectral evolution of said ratio (r). - View Dependent Claims (18)
-
Specification